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Disturbed inhibitory synaptic transmission has functional impacts on neurodevelopmental and psychiatric disorders. An essential mechanism for modulating inhibitory synaptic transmission is alteration of the postsynaptic abundance of GABAARs, which are stabilized by postsynaptic scaffold proteins and recruited by presynaptic signals. However, how GABAergic neurons trigger signals to transsynaptically recruit GABAARs remains elusive. Here, we show that UNC-43/CaMKII functions at GABAergic neurons to recruit GABAARs and modulate inhibitory synaptic transmission at C. elegans neuromuscular junctions. We demonstrate that UNC-43 promotes presynaptic MADD-4B/Punctin secretion and NRX-1α/Neurexin surface delivery. Together, MADD-4B and NRX-1α recruit postsynaptic NLG-1/Neuroligin and stabilize GABAARs. Further, the excitation of GABAergic neurons potentiates the recruitment of NLG-1-stabilized-GABAARs, which depends on UNC-43, MADD-4B, and NRX-1. These data all support that UNC-43 triggers MADD-4B and NRX-1α, which act as anterograde signals to recruit postsynaptic GABAARs. Thus, our findings elucidate a mechanism for pre- and postsynaptic communication and inhibitory synaptic transmission and plasticity.

Xylaria wuzhishanensis Y.P. Wu & Q.R. Li, sp. nov. (Fig. 5) MycoBank number: MB 842170 Type:— CHINA, Hainan Province, Wuzhishan City, Wuzhishan Nature Reserve (18.541805°N, 109.412245°E), elev. 892 m, on dead wood of a plant roots (Oleaceae sp.), November 2020, Youpeng Wu and Lili Liu, 2020WZS35 (GMB0074, holotype; KUN-HKAS 12634, isotype; ex-type living culture, GMBC0074). Etymology: Referring to its collection location, Wuzhishan Mountain from where the species was first isolated (China). Saprobic on dead wood roots, forming on the host surface. Sexual morph: Stromata 0.3–0.8 cm long × 0.6–1.2 cm broad (x = 0.6 × 0.8 cm, n = 10), semiglobular or irregularly globose, whole stromata up to with flattened or slightly convex top. Surface of stromata black, with raised blackish dots. Perithecia 300–600 μm high × 200–400 μm diam. (x = 400 × 300 μm, n = 10), oval to spherical, embedded, closely arranged, interior white. Ostioles papillate, surrounded with white tissue. Asci 235–366 × 11–20 μm (x = 293 × 14.2 μm, n = 30), 8-spored, unitunicate, cylindrical, long-stipitate, apically rounded, with a J+, rectangular or urn-shaped, apical ring, blue staining in Melzer’s reagent, 6.7–10.5 μm (x = 8.7 μm, n = 30) high, 4.2–6.5 μm (x = 5.3 μm, n = 30) wide. Ascospores 23–30.5 × 7–9 μm (x = 26.5 × 8 μm, n=30), brown to black, unicellular, ellipsoid to inequilateral, with broadly rounded ends, smooth, with a conspicuous slanted germ slit nearly one-third spore-length, lacking appendages and sheaths. Asexual morph: Undetermined. Culture characteristics: Colonies on OA reaching 3–4 mm diam. after 2 weeks at 25 °C. White at first, white at first, upright, velvety with irregular outgrowths or furrows, with a peripheral fan-shaped extension spreading toward the edge; reverse light grey in the center, white marginal area. After 4 weeks, colonies on OA reaching 9 cm diam., white greyish, velvety or inflorescence, appressed with entire margins; reverse black, with brownish ring. No conidia were observed. Notes: Based on the multi-gene phylogenetic analyses (Fig. 1), X. wuzhishanensis is most closely related to X. schweinitzii. Morphologically, X. wuzhishanensis differs from X. schweinitzii by its semi-globular or irregularly globose stromata. Xylaria wuzhishanensis shows similar traits of X. atrosphaerica (Cooke & Massee) Callan & J.D. Rogers, X. globosa (Spreng. ex Fr.: Fr.) Mont., and X. lepidota Y.M. Ju et al. with semiglobular or irregularly globose stromata. But, X. wuzhishanensis can distinguish from X. atrosphaerica by its larger ascospores (23–30.5 × 7–9 μm vs. 17–25 × 6–10 μm) with a shorter germ slit (Callan et al. 1990). The surface of stroma lacks crackle of X. wuzhishanensis, which can make a distinction between X. globosa and X. lepidota (Ju et al. 2009, Fournier et al. 2018)., Published as part of Wu, You-Peng, Pi, Yin-Hui, Long, Si-Han, Liu, Li-Li, Zhang, Xu, Long, Qing-De, Lin, Yan, Kang, Ying-Qian, Kang, Ji-Chuan, Wijayawardene, Nalin N. & Li, Qi-Rui, 2022, Morphology and phylogeny reveal two novel Xylaria (Xylariaceae) species from China, pp. 130-146 in Phytotaxa 550 (2) on page 141, DOI: 10.11646/phytotaxa.550.2.3, http://zenodo.org/record/6641065, {"references":["Callan, B. E. & Rogers, J. D. (1990) Teleomorph-anamorph connections and correlations in some Xylaria species. Mycotaxon 36: 343 - 369.","Ju, Y. M., Hsieh, H. M., Vasilyeva, L. & Akulov, A. (2009) Three new Xylaria species from Russian Far East. Mycologia 101: 548 - 553. http: // doi. org / 10.3852 / 08 - 188","Fournier, J., Lechat, C. & Courtecuisse, R. (2018) The genus Xylaria sensu lato (Xylariaceae) in Guadeloupe and Martinique (French West Indies) I. Taxa with penzigioid stromata. Ascomycete. org 10 (4): 131 - 176. http: // doi. org / 10.25664 / ART- 0239"]}

Xylaria sylvatica Y.P. Wu & Q.R. Li, sp. nov. (Fig. 4) MycoBank number: MB 842171 Type:— CHINA. Guizhou Province: Guiyang City, Guiyang Forest Park (26.2329°N, 106.451958°E), elev. 1142 m, on dead wood of unidentified plant, June 2021, Youpeng Wu, 2021GYSLGY6 (GMB0076, holotype; KUN-HKAS 122632, isotype; ex-type living culture, GMBC0076). Etymology: Refers to a forest habitat for specimen collection. Saprobic on dead wood, forming on the host surface. Sexual morph: Stromata 0.6–1.7 cm long × 0.2–0.5 cm broad (x = 1.2 × 0.4 cm, n = 10), upright, usually solitary, unbranched, cylindrical or clavate, fertile inflated at apex, texture soft, internally white. Surface of stromata gray to black, conspicuous cracked. Stalk well defined and easy to distinguish. Perithecia 500–700 μm high × 300–700 μm broad (x = 600 × 400 μm, n = 10), oval, sphaerical to subsphaerical, embedded, closely arranged, tissue between the perithecia is white. Ostioles inconspicuous. Asci 224–313 × 10.5–20.5 μm (x = 260 × 15 μm, n = 30), 8-spored, unitunicate, cylindrical, long-stipitate, apically rounded, with a J+, wedge-shaped apical ring, blue staining in Melzer’s reagent, 9–15 μm (x = 12.2 μm, n = 30) high, 4–7 μm (mean = 5.3 μm, n = 30) wide. Ascospores 23–28.5 × 7–9.5 μm (x = 25 × 8 μm, n = 30), green grey, unicellular, ellipsoid to inequilateral, with broadly rounded ends, smooth, with a sigmoid germ slit nearly half spore-length, lacking appendages and sheaths. Asexual morph: Undetermined. Culture characteristics: Colonies on OA reaching 3–4 mm diam. after 2 weeks at 25 °C. White at first, with regular margins, upright, velvety, with irregular outgrowths or furrows, with a peripheral fan-shaped extension spreading toward the edge; reverse blackish-brown in the center, white marginal area. After 4 weeks, Colonies on OA reaching 9 cm diam., white greyish, velvety or inflorescence, appressed with entire margins; reverse black, with brownish ring. No conidia were observed. Notes: Phylogenetic analyses (Fig. 1) indicated that X. sylvatica was closely related to X. spinulosa and X. haemorrhoidalis but formed a distinct lineage. However, X. sylvatica is distinguish from X. spinulosa by its lacking long thorns on the stromatal surface, and larger ascospores (23–28.5 × 7–9.5 μm vs. 19–23 × 6.5–8.5 μm) with a sigmoid germ slit. Xylaria sylvatica differs from X. haemorrhoidalis by its upright, solitary, unbranched, cylindrical or clavate stromata (Li et al. 2017). Morphologically, Xylaria sylvatica shows similar traits of X. martinicensis J. Fourn. & Lechat., and X. squamulosa F. San Martín & J.D. Rogers., with upright, long stipitate, cylindrical or clavate stromata with fertile inflated at apex, conspicuous cracked or wrinkled on the surface of stromata. But, X. martinicensis have smaller ascospores (13–16.5 × 6–7.5 μm vs. 23–28.5 × 7–9.5 μm), with a narrow but conspicuous, straight, longitudinally oriented germ slit, which can make a distinction for X. sylvatica (Fournier et al. 2020). Xylaria squamulosa differs from X. sylvatica by larger ascospores (29–40 × 11–14 μm vs. 23–28.5 × 7–9.5 μm) with a straight germ slit nearly spore-length (San Martín et al. 1989)., Published as part of Wu, You-Peng, Pi, Yin-Hui, Long, Si-Han, Liu, Li-Li, Zhang, Xu, Long, Qing-De, Lin, Yan, Kang, Ying-Qian, Kang, Ji-Chuan, Wijayawardene, Nalin N. & Li, Qi-Rui, 2022, Morphology and phylogeny reveal two novel Xylaria (Xylariaceae) species from China, pp. 130-146 in Phytotaxa 550 (2) on pages 137-141, DOI: 10.11646/phytotaxa.550.2.3, http://zenodo.org/record/6641065, {"references":["Li, Q. R., Liu, L. L., Zhang, X., Shen, X. C. & Kang, J. C. (2017) Xylaria spinulosa sp. nov. and X. atrosphaerica from southern China. Mycosphere 8 (8): 1070 - 1079. http: // doi. org / 10.5943 / mycosphere / 8 / 8 / 8","Fournier, J., Lechat, C. & Courtecuisse, R. (2020) The genus Xylaria sensu lato (Xylariaceae) in Guadeloupe and Martinique (French West Indies) III. Taxa with slender upright stromata. Ascomycete. org 12 (3): 81 - 164. http: // doi. org / 10.25664 / ART- 0302","San Martin, G. F. & Rogers, J. D. (1989) A preliminary account of Xylaria of Mexico. Mycotaxon 34 (2): 368."]}

Xylaria atrosphaerica (Cooke & Massee) Callan & J.D. Rogers, Mycotaxon 36 (2): 349 (1990) (Fig. 2) Synonymy: Hypoxylon atrosphaericum Cooke & Massee, Grevillea 22(no. 103): 68 (1894) Penzigia atrosphaerica (Cooke & Massee) J.N. Mill., Monograph Univ. Puerto Rico, Series B 2: 212 (1934) Kretzschmaria atrosphaerica (Cooke & Massee) P.M.D. Martin, Jl S. Afr. Bot. 36(2): 79 (1970) Kretzschmaria atrosphaerica (Cooke & Massee) P.M.D. Martin, Jl S. Afr. Bot. 42(1): 74 (1976) MycoBank number: MB 127393 Saprobic on dead wood, forming on the host surface. Sexual morph: Stromata semiglobular or irregularly globose, pulvinate, 0.4‒1.8 mm high × 1.4‒3.2 mm broad (x = 1.4 × 2.3 mm, n = 10), with flattened or slightly convex top. Exterior grey dark to black, roughened by fine cracks and ostioles; interior whithish to light grey. Perithecia 0.3‒0.8 mm diam., completely immersed, sphaerical. Ostioles inconspicuous. Asci 182‒288 × 12.3‒20 μm (x = 237 × 16.1 μm, n = 30), unitunicate, 8-spored, cylindrical, long-stipitate, apically rounded, with a J +, wedge-shaped apical ring, blue staining in Melzer’s reagent, 7–12 μm (x = 10 μm, n = 30) high, 3.5–7 μm (x = 5.4 μm, n = 30) wide. Ascospores 20.5–25.5 × 6.5–10 μm (x = 22.7 × 7.8 μm, n = 30), brownish-black, unicellular, ellipsoid to inequilateral, with broadly rounded ends, smooth, with a sigmoid germ slit nearly half spore-length, lacking appendages and sheaths. Asexual morph: Undetermined. Specimens examined: CHINA, Guizhou Province, Duyun City, Doupengshan Nature Reserve (26.223062°N, 107.22846°E), elev. 1086 m, on dead wood of unidentified plant, June 2021, Youpeng Wu, 2021DPS13 (GMB0077, KUN-HKAS 122633; living culture, GMBC 0077). Culture characteristics: Colonies on OA reaching 4–5 mm diam. after 2 weeks at 25 ° C. White at first, with regular margins, becoming moderately radiating furrows spreading toward the edge, medium becoming black from central; reverse greyish black ring in the center, white marginal area. After 4 weeks, colonies on OA reaching 9 cm diam., white, velvety, appressed with entire margins; reverse dark black. No conidia were observed. Notes: Hypoxylon atrosphaericum Cooke & Massee collected from Queensland was described originally by Cooke (1894). Rogers et al. (1987) described the asexual morph of Penzigia atrosphaerica collected from Indonesia. However, based primarily on the nature of cultures, Callan & Rogers (1990) placed them in the genus Xylaria. Morphologically, our new collection (GMB0077) is congruent with X. atrosphaerica having semi-globular or irregularly globose stromata, grey dark to black, internally white; surface roughened by fine cracks and ostioles and perithecial mounds inconspicuous, brownish-black, ellipsoid-inequilateral, smooth ascospores (17–25 × 6–10 μm), with oblique to spiral germ slit, nearly 1/2 spore-length, lacking sheaths and appendages. Phylogenetic analyses showed that GMB0077 resembles with X. atrosphaerica (HAST 91111214) with high statistical support (100% ML, 1.00 BYPP; Fig. 1)., Published as part of Wu, You-Peng, Pi, Yin-Hui, Long, Si-Han, Liu, Li-Li, Zhang, Xu, Long, Qing-De, Lin, Yan, Kang, Ying-Qian, Kang, Ji-Chuan, Wijayawardene, Nalin N. & Li, Qi-Rui, 2022, Morphology and phylogeny reveal two novel Xylaria (Xylariaceae) species from China, pp. 130-146 in Phytotaxa 550 (2) on page 134, DOI: 10.11646/phytotaxa.550.2.3, http://zenodo.org/record/6641065, {"references":["Rogers, J. D., Callan, B. E. & Samuels, G. J. (1987) The Xylariaceae of the rain forests of north Sulawesi (Indonesia). Mycotaxon 29: 113 - 172. https: // doi. org / 10.1007 / BF 00436682","Callan, B. E. & Rogers, J. D. (1990) Teleomorph-anamorph connections and correlations in some Xylaria species. Mycotaxon 36: 343 - 369."]}

Xylaria sylvatica Y.P. Wu & Q.R. Li, sp. nov. (Fig. 4) MycoBank number: MB 842171 Type:— CHINA. Guizhou Province: Guiyang City, Guiyang Forest Park (26.2329°N, 106.451958°E), elev. 1142 m, on dead wood of unidentified plant, June 2021, Youpeng Wu, 2021GYSLGY6 (GMB0076, holotype; KUN-HKAS 122632, isotype; ex-type living culture, GMBC0076). Etymology: Refers to a forest habitat for specimen collection. Saprobic on dead wood, forming on the host surface. Sexual morph: Stromata 0.6–1.7 cm long × 0.2–0.5 cm broad (x = 1.2 × 0.4 cm, n = 10), upright, usually solitary, unbranched, cylindrical or clavate, fertile inflated at apex, texture soft, internally white. Surface of stromata gray to black, conspicuous cracked. Stalk well defined and easy to distinguish. Perithecia 500–700 μm high × 300–700 μm broad (x = 600 × 400 μm, n = 10), oval, sphaerical to subsphaerical, embedded, closely arranged, tissue between the perithecia is white. Ostioles inconspicuous. Asci 224–313 × 10.5–20.5 μm (x = 260 × 15 μm, n = 30), 8-spored, unitunicate, cylindrical, long-stipitate, apically rounded, with a J+, wedge-shaped apical ring, blue staining in Melzer’s reagent, 9–15 μm (x = 12.2 μm, n = 30) high, 4–7 μm (mean = 5.3 μm, n = 30) wide. Ascospores 23–28.5 × 7–9.5 μm (x = 25 × 8 μm, n = 30), green grey, unicellular, ellipsoid to inequilateral, with broadly rounded ends, smooth, with a sigmoid germ slit nearly half spore-length, lacking appendages and sheaths. Asexual morph: Undetermined. Culture characteristics: Colonies on OA reaching 3–4 mm diam. after 2 weeks at 25 °C. White at first, with regular margins, upright, velvety, with irregular outgrowths or furrows, with a peripheral fan-shaped extension spreading toward the edge; reverse blackish-brown in the center, white marginal area. After 4 weeks, Colonies on OA reaching 9 cm diam., white greyish, velvety or inflorescence, appressed with entire margins; reverse black, with brownish ring. No conidia were observed. Notes: Phylogenetic analyses (Fig. 1) indicated that X. sylvatica was closely related to X. spinulosa and X. haemorrhoidalis but formed a distinct lineage. However, X. sylvatica is distinguish from X. spinulosa by its lacking long thorns on the stromatal surface, and larger ascospores (23–28.5 × 7–9.5 μm vs. 19–23 × 6.5–8.5 μm) with a sigmoid germ slit. Xylaria sylvatica differs from X. haemorrhoidalis by its upright, solitary, unbranched, cylindrical or clavate stromata (Li et al. 2017). Morphologically, Xylaria sylvatica shows similar traits of X. martinicensis J. Fourn. & Lechat., and X. squamulosa F. San Martín & J.D. Rogers., with upright, long stipitate, cylindrical or clavate stromata with fertile inflated at apex, conspicuous cracked or wrinkled on the surface of stromata. But, X. martinicensis have smaller ascospores (13–16.5 × 6–7.5 μm vs. 23–28.5 × 7–9.5 μm), with a narrow but conspicuous, straight, longitudinally oriented germ slit, which can make a distinction for X. sylvatica (Fournier et al. 2020). Xylaria squamulosa differs from X. sylvatica by larger ascospores (29–40 × 11–14 μm vs. 23–28.5 × 7–9.5 μm) with a straight germ slit nearly spore-length (San Martín et al. 1989).

Xylaria cubensis (Mont.) Fr., Nova Acta Regia Soc. Sci. Upsal. (Ser. 3) 1: 126. 1851; sensu Rogers (1984) (Fig. 3) Synonymy: Hypoxylon cubense Mont., Annls Sci. Nat., Bot., sér. 2 13: 345 (1840) MycoBank number: MB 179243 Saprobic on dead tree trunk, forming on the host surface. Sexual morph: Stromata solitary, cylindric-clavate, usually unbranched, 2.2–5.8 cm long × 0.6–1.2. cm broad (x = 3.6 × 0.8 cm, n = 10), with short or long stipe from a pannose base, externally copper brown to brownish-black, internally white. Surface smooth to slightly rough with fine cracks. Perithecia ovoid, 0.4–0.8 mm diam., ostioles inconspicuous to conspicuous, prominent. Ostioles papillae. Asci 107– 162 × 5.3‒8.2 μm (x = 124 × 6.8 μm, n = 30), unitunicate, 8-spored, cylindrical, long-stipitate, apically rounded, with a J +, rectangular, apical ring, blue staining in Melzer’s reagent, 1.5–2.5 μm (x = 2.2 μm, n = 30) high, 1.5–2 μm (x = 1.8 μm, n = 30) wide. Ascospores 8–9.5 × 4–5 μm (x = 8.5 × 4.5 μm, n = 30), brown to dark brown, unicellular, ellipsoid-inequilateral, with widely rounded ends, smooth, with a straight central germ slit along much less than sporelength, lacking appendages and sheaths. Asexual morph: Undetermined. Specimens examined: CHINA, Hainan Province, Haikou City, Huoshankou Geological Park (19.554365°N, 110.13203°E), elev. 152 m, on dead wood of unknown plant roots, November 2020, Youpeng Wu and Lili Liu, 2020HSK4 (GMB0075, KUN-HKAS 122631; living culture GMBC 0075). Culture characteristics: Colonies on OA reaching 4–5 mm diam. after 2 weeks at 25 ° C. White at first, with regular margins, then with a peripheral ring-shaped extension spreading toward the edge of the Petri dish; reverse milky white in the center, light white marginal area. After 4 weeks, colonies on OA reaching 9 cm, stromata arising from concentric zones, cylindrical, tapering upwards, flexuous, unbranched; reverse light grey, emerge black dots. No conidia were observed. Notes: Xylaria cubensis is a common species and was reported from Africa, North and South America, Asia, Oceania and China (Ma et al. 2012). Xylaria cubensis is mainly characterized by its smooth surface with papillate ostioles, copper-colored, brown or brownish-black clavate stromata with rounded fertile apices and small ascospores mostly with unclear germ slit (Rogers 1984), which has been reported from Taiwan (Ju et al. 1999) and Guizhou, Jilin, Yunnan provinces in China (Ma et al. 2012). Our specimens examined in this study display the same characters of X. cubensis described by Rogers (1984) and Ma et al. (2012), such as long stipe from a pannose base, with papillate ostioles of stromata surface, externally copper brown to brownish-black, internally white; ascospores with unclear germ slit less than spore-length, lacking appendages and sheaths. Phylogenetic analyses of a combined alignment of β-tubulin, rpb 2 and α-actin genes showed that the strain GMB0075 grouped with X. cubensis (HAST 515) with high statistical support (100% ML, 1.00 BYPP; Fig. 1). This is the first record of X. cubensis from Hainan province, China., Published as part of Wu, You-Peng, Pi, Yin-Hui, Long, Si-Han, Liu, Li-Li, Zhang, Xu, Long, Qing-De, Lin, Yan, Kang, Ying-Qian, Kang, Ji-Chuan, Wijayawardene, Nalin N. & Li, Qi-Rui, 2022, Morphology and phylogeny reveal two novel Xylaria (Xylariaceae) species from China, pp. 130-146 in Phytotaxa 550 (2) on page 137, DOI: 10.11646/phytotaxa.550.2.3, http://zenodo.org/record/6641065, {"references":["Rogers, J. D. (1984) Xylaria cubensis and its anamorph Xylocoremium flabelliforme, Xylaria allantoidea, and Xylaria poitei in continental United States. Mycologia 76: 912 - 923. https: // doi. org / 10.1080 / 00275514.1984.12023929","Ju, Y. M. & Rogers, J. D. (1999) The Xylariaceae of Taiwan (excluding Anthostomella). Mycotaxon 73: 343 - 440."]}

Astrocystis multiloculata Y.P. Wu & Q.R. Li, sp. nov. (Fig. 4) MycoBank: MB839643 Type:— CHINA. Yunnan Province: Baoshan City, Lancang River Nature Reserve (24.51946°N, 99.415778°E), elev. 1747 m, on dead bamboo culms, 10 October 2019, Yinhui Pi2019LC129 (GMB0033, holotype; KUN-HKAS 112661, isotype; ex-type living culture, GMBC0033). Saprobic on the surface of dead bamboo culms, visible as black raised lump on the host. Sexual morph: Stromata erumpent, effused lump with flat top, irregular in outline, with a discoid black base, containing many perithecia (mostly more than 8, with independent ostiole), gregarious or solitary, scattered, carbonaceous, embedded on the host surface, 0.6–3.0 mm diam., 0.6–2.4 mm high, smooth, tissue between perithecia woody. Perithecia spherical to obovate, without carbonaceous stromatal tissue surrounding the individual perithecia. Ostioles at the same level as stromatal surface, with slight papillate openings. Asci 120–142 × 7–12.5 μm (mean 131 × 9.5 μm, n = 30), 8-spored, unitunicate, cylindrical, short-pedicellate, persistent, apically rounded, with J+, square-shaped apical apparatus, blue staining in Melzer’s reagent, 3–5 μm (mean 3.5 μm, n = 30) high, 3.0–4.5 μm (mean 3.3 μm, n = 30) wide. Ascospores 19–25 × 7–11 μm (mean 21.5 × 8.7 μm, n = 30), uniseriate, dark reddish brown, aseptate, equilateral ellipsoid, with rounded ends, smooth, with a straight germ slit slightly less than full-length, lacking appendages and sheath. Asexual morph: undetermined. Culture characteristics:— Ascospores germinated on PDA within 24 hours, 25 °C, colonies, dense but thinning towards the edge, edge irregular, white from above, reverse similar in colour. No conidia were observed on PDA or OA media. Habitat/Distribution:— Known to inhabit dead bamboo, Yunnan Province, China. Etymology:— Refers to its stromata containing many ascomata. Other specimens examined:— CHINA. Yunnan Province: Baoshan City, Lancang River Nature Reserve (25.13409°N, 99.352676°E), elev. 2546 m, on dead bamboo culms, 10 October 2019, Yinhui Pi, collection number: 2019LC166 (GMB0032; living culture, GMBC0032). Notes:— Morphologically, A. multiloculata can be distinguished from other Astrocystis species by its superficial stromata, which contain many perithecia (mostly more than 8, with independent ostiole), and larger ascospores (19–25 × 7–11 μm). Phylogenetic analyses based on ITS, RPB2, β-tubulin and α-actin dataset show that A. multiloculata formed a well-separated clade to A. cocoes with high bootstrap support (Fig. 1). Astrocystis multiloculata shows a close relationship with Kretzschmariella in terms of stromata. Both have stromata containing many perithecia, and ascospores with straight germ slit slightly less than spore-length, but K. culmorum (Cooke) Y.M. Ju & J.D. Rogers (Ju & Rogers 1994) and K. guaduae Viégas (Viégas 1994) usually bear a cellular appendage on immature ascospores which distinguish them from A. multiloculata. Moreover, the phylogenetic tree shows that it is more reasonable to place A. multiloculata in Astrocystis., Published as part of Wu, You-Peng, Pi, Yin-Hui, Long, Si-Han, Lin, Yan, Long, Qing-De, Kang, Ji-Chuan, Kang, Ying-Qian, Shen, Xiang-Chun, Wijayawardene, Nalin N., Zhang, Xu & Li, Qi-Rui, 2021, Morphological and phylogenetic study of five species of Astrocystis and Collodiscula on bamboo, pp. 265-284 in Phytotaxa 522 (4) on page 276, DOI: 10.11646/phytotaxa.522.4.1, http://zenodo.org/record/5565846, {"references":["Ju, Y. M. & Rogers, J. D. (1994) Kretzschmariella culmorum. Mycotaxon 51: 242.","Viegas, K. G. (1994) Kretzschmariella guaduae. Bragantia 4: 105."]}

Astrocystis cocoes (Henn.) Laessøe & Spooner, Kew Bull. 49(1): 27 (1994) (Fig. 6) ≡ Rosellinia cocoes Henn., Hedwigia 47(4): 256 (1908) MycoBank: MB580660 Saprobic on the surface of dead bamboo stalk, visible as black raised spots on the host. Sexual morph: Stromata erumpent, solitary or gregarious, not or somewhat confluent, black, carbonaceous, containing 1 ascoma, almost conical with a round apex, 0.4–0.6 mm diam., 0.5–0.8 mm high, with an outer stellate layer; persistent pale squamules from host cuticle, apex smooth and sometimes almost annulate with a minutely papillate ostiole. Asci 118–129 × 6.6–8.5 μm (mean 123 × 7.6 μm, n = 30), 8-spored, spore bearing part cylindrical, stipe short and tapering, apically rounded, with a discoid, subapical, J+ apical apparatus, with sides tapering to the base, blue staining in Melzer’s reagent, 2.4–3.5 μm (mean 2.8 μm, n = 30) high, 2.0–3.2 μm (mean 2.8 μm, n = 30) wide. Ascospores 18.1–22.8 × 5.5–6.0 μm (mean 19.8 × 6.2 μm, n = 30), overlapping uniseriate, aseptate, dark reddish brown, inequilaterally fusiform, with one or both ends beaked, flattened side slightly convex, with a germ slit on flattened side, less than full spore-length, with thin mucilaginous sheath and pad-like polar appendages. Asexual morph: undetermined. Specimens examined:— CHINA. Hainan Province: Wuzhishan City, Wuzhishan Nature Reserve (18.541959°N, 109.405444°E), elev. 767 m, on dead bamboo culms, 11 October 2020, Q.R. Li 2020WZS64-3 (GMB0037; KUN-HKAS 112701; living culture, GMBC0037). Culture characteristics:— Ascospores germinated on PDA within 24 hours at 25 °C, colonies, dense but thinning towards the edge, edge irregular, white from above, reverse similar in colour. No conidia were observed on PDA or OA media. Habitat/Distribution:— Known to inhabit dead bamboo, Brazil, China, India, Philippines. Notes:— Astrocystis cocoes was described on dead branches of Cocos nucifera (Laessøe & Spooner 1994) collected from Philippines. Our new collection (GMB0037) morphologically resembles A. cocoes. Astrocystis cocoes is distinct from A. sublimbata by its size of ascospores (15–19 × 6.5–8.5 μm vs 17–22 × 7.5–9.5 μm). Moreover, the ascospores of A. sublimbata do not possess a mucilaginous sheath and pad-like polar appendages (Smith & Hyde 2001). Phylogenetic analyses of the combined ITS, RPB2, β-tubulin and α-actin genes show that GMBC0037 groups with A. cocoes with high support (100% ML, 1.00 BYPP; Fig. 1). This is the first report of A. cocoes from China., Published as part of Wu, You-Peng, Pi, Yin-Hui, Long, Si-Han, Lin, Yan, Long, Qing-De, Kang, Ji-Chuan, Kang, Ying-Qian, Shen, Xiang-Chun, Wijayawardene, Nalin N., Zhang, Xu & Li, Qi-Rui, 2021, Morphological and phylogenetic study of five species of Astrocystis and Collodiscula on bamboo, pp. 265-284 in Phytotaxa 522 (4) on page 280, DOI: 10.11646/phytotaxa.522.4.1, http://zenodo.org/record/5565846, {"references":["Laessoe, T. & Spooner, B. M. (1994) Rosellinia & Astrocystis (Xylariaceae): new species and generic concepts. Kew Bulletin 49: 1 - 70. http: // doi. org / 10.2307 / 4110199","Smith, G. & Hyde, K. D. (2001) Fungi from palms. XLIX. Astrocystis, Biscogniauxia, Cyanopulvis, Hypoxylon, Nemania, Guestia, Rosellinia and Stilbohypoxylon. Fungal Diversity 7: 89 - 127. http: // doi. org / 10.1002 / yea. 733"]}

Astrocystis bambusicola R.H. Perera & K.D. Hyde, Fungal Diversity 87: 173 (2017) (Fig. 5) MycoBank: MB552219 Saprobic on the surface of dead bamboo stalk, visible as black raised spots on the host. Sexual morph: Stromata erumpent, scattered, superficial, subglobose to dome-shaped, blackened, carbonaceous, with papillate ostioles, containing 1–3 ascomata, 0.20–0.73 mm diam., 0.13–0.20 mm high. Perithecia comprising black, fragile, carbonaceous tissue. Asci 119–132 × 8–11.5 μm (mean 124 × 9.6 μm, n = 30), 8-spored, unitunicate, cylindrical, with a short pedicel, persistent, apically rounded, with J+, square-shaped apical apparatus, blue staining in Melzer’s reagent, 3–4.5 μm (mean 3.2 μm, n = 30) high, 2.0–3.5 μm (mean 2.8 μm, n = 30) wide. Ascospores 18.0–26 × 6.5–11 μm (mean 20.8 × 8.0 μm, n = 30), uniseriate, ellipsoid, aseptate, brown to dark brown, guttulate, smooth-walled, with a germ slit slightly less than full spore-length, lacking appendages and sheath. Asexual morph: undetermined. Specimens examined:— CHINA. Guizhou Province: Tongren City, Fanjingshan Nature Reserve (27.544623°N, 108.454326°E), elev. 912 m, on dead bamboo culms, 10 October 2020, Q.R. Li 2020FJS35 (GMB0036, KUN-HKAS 112691; living culture, GMBC0036). Culture characteristics:— Ascospores germinated on PDA within 24 hours at 25 °C, colonies, dense but thinning towards the edge, edge irregular, white from above, reverse similar in colour. No conidia were observed on PDA or OA media. Habitat/Distribution:— Known to inhabit dead bamboo, China, Thailand. Notes:— Morphologically, A. bambusicola differs from A. mirabilis and A. bambusae by its superficial stromata, larger ascospores and smaller asci. Phylogenetic analyses of a combined ITS, RPB2, β-tubulin and α-actin sequences dataset shows that our strain GMB0036 clades with the type strain of A. bambusicola (MFLUCC 17-0127) with high statistical support (99% ML, 0.99 BYPP; Fig. 1). The new collection morphologically resembles A. bambusicola. Thus, we identify it as A. bambusicola which has been reported in Thailand (Hyde et al. 2017) and Yunnan, China (Hyde et al. 2019)., Published as part of Wu, You-Peng, Pi, Yin-Hui, Long, Si-Han, Lin, Yan, Long, Qing-De, Kang, Ji-Chuan, Kang, Ying-Qian, Shen, Xiang-Chun, Wijayawardene, Nalin N., Zhang, Xu & Li, Qi-Rui, 2021, Morphological and phylogenetic study of five species of Astrocystis and Collodiscula on bamboo, pp. 265-284 in Phytotaxa 522 (4) on pages 276-280, DOI: 10.11646/phytotaxa.522.4.1, http://zenodo.org/record/5565846, {"references":["Hyde, K. D., Norphanphoun, C., Abreu, V. P., Bazzicalupo, A. & Mortimer, P. E. (2017) Fungal diversity notes 603 - 708: taxonomic and phylogenetic notes on genera and species. Fungal Diversity 87: 1 - 235. http: // doi. org / 10.1007 / s 13225 - 017 - 0391 - 3","Daranagama, D. A., Camporesi, E., Tian, Q., Liu, X., Chamyuang, S., Stadler, M. & Hyde, K. D. (2015) Anthostomella is polyphyletic comprising several genera in Xylariaceae. Fungal Diversity 73: 203 - 238. http: // doi. org / 10.1007 / s 13225 - 015 - 0329 - 6","Fournier, J., Lechat, C. & Courtecuisse, R. (2018) The genera Kretzschmariella and Nemania (Xylariaceae) in Guadeloupe and Martinique (French West Indies). Ascomycete. org 10: 1 - 47. http: // doi. org / 10.25664 / ART- 0226","Hyde, K. D., Tennakoon, D. S., Jeewon, R., Bhat, D. J. & Doilom, M. (2019) Fungal diversity notes 1036 - 1150: taxonomic and phylogenetic contributions on genera and species of fungal taxa. Fungal Diversity 96: 1 - 242. http: // doi. org / 10.1007 / s 13225 - 019 - 00429 - 2"]}

Collodiscula lancangjiangensis Y.P. Wu & Q.R. Li, sp. nov. (Fig. 2) MycoBank: MB839642 Type:— CHINA. Yunnan Province: Baoshan City, Lancang River Nature Reserve (28.72997°N, 99.361083°E), elev. 2674 m, on dead bamboo culms, 10 October 2019, Yinhui Pi 2019LC157 (GMB0030, holotype; KUN-HKAS 112663, isotype; ex-type living culture, GMBC0030). Saprobic on dead bamboo culms. Sexual morph: Stromata scattered or gregarious, solitary, superficial, black, hexagonal prism, 0.5–0.8 mm diam., 0.3–0.6 mm high, containing 1–2 ascomata, with a circle of black tissue at the bottom, with a papillary ostiole. External stromatal layer black, carbonaceous, easily chipped away to reveal the thin, black ascomata. Ostioles papillate in the centre, black. Perithecia subglobose to globose, 0.4–0.8 mm diam., 0.3–0.6 mm high. Asci 145–175 × 9–16 μm (mean 162 × 11.8 μm, n = 30), 8-spored, unitunicate, short-pedicellate, apically rounded with a J+, wedge-shaped apical apparatus, blue staining in Melzer’s reagent, 3.0–3.5 μm (mean 3.2 μm, n = 30) high, 1.5–2.0 μm (mean 1.7 μm, n = 30) broad. Ascospores 26–36.5 × 5–7.5 μm (mean 31 × 6.5 μm, n = 30), overlapping uniseriate, fusiform, equilateral, 3-septate, not constricted at septa, yellowish brown, blunt at both ends, smooth-walled, lacking germ slits or appendages. Asexual morph: undetermined. ...continued on the next page Culture characteristics:— Ascospores germinated on PDA within 24 hours at 25 °C, colonies, dense but thinning towards the edge, edge irregular, white from above, reverse similar in colour. No conidia were observed on PDA or oat agar (OA) media. Habitat/Distribution:— Known to inhabit dead bamboo, Yunnan Province, China. Etymology:— Refers to the location where the specimens were collected, Lancang River Nature Reserve. Other material examined:— CHINA. Yunnan Province: Baoshan City, Lancang River Nature Reserve (25.7880°N, 99.352864°E), elev. 2656 m, on dead bamboo culms, 10 October 2019, Yinhui Pi 2019LC352 (GMB0031, KUN-HKAS 112678; no culture was obtained; DNA was extracted directly from asci and ascospores); Yunnan Province: Baoshan City, Lancang River Nature Reserve (25.033204°N, 99.361543°E), elev. 2676 m, on dead bamboo culms, 10 October 2019, Yinhui Pi 2019LC205 (GMB0038; KUN-HKAS 112669; no culture was obtained). Notes:— To date, six species of Collodiscula have been reported (Hino & Katumoto 1955, Li et al. 2015a, b, Hyde et al. 2017, Xie et al. 2020). Collodiscula lancangjiangensis has 3-septate ascospores as does C. fangjingshanensis and C. leigongshanensis, which were collected from China. However, C. lancangjiangensis has larger ascospores than C. fangjingshanensis (19–25.5 × 4.5–6 μm) and C. leigongshanensis (28–35 × 8–10.5 μm). Phylogenetic analyses (Fig. 1) indicates that C. lancangjiangensis is closely related to C. japonica with high bootstrap support and PP values (92% ML, 0.99 BYPP; Fig. 1), but forms a distinct lineage., Published as part of Wu, You-Peng, Pi, Yin-Hui, Long, Si-Han, Lin, Yan, Long, Qing-De, Kang, Ji-Chuan, Kang, Ying-Qian, Shen, Xiang-Chun, Wijayawardene, Nalin N., Zhang, Xu & Li, Qi-Rui, 2021, Morphological and phylogenetic study of five species of Astrocystis and Collodiscula on bamboo, pp. 265-284 in Phytotaxa 522 (4) on pages 268-273, DOI: 10.11646/phytotaxa.522.4.1, http://zenodo.org/record/5565846, {"references":["Hsieh, H. M., Lin, C. R., Fang, M. J., Rogers, J. D., Fournier, J., Lechat, C. & Ju, Y. M. (2010) Phylogenetic status of Xylaria subgenus Pseudoxylaria among taxa of the subfamily Xylarioideae (Xylariaceae) and phylogeny of the taxa involved in the subfamily. Molecular Phylogenetics and Evolution 54: 957 - 969. http: // doi. org / 10.1016 / j. ympev. 2009.12.015","Hyde, K. D., Norphanphoun, C., Abreu, V. P., Bazzicalupo, A. & Mortimer, P. E. (2017) Fungal diversity notes 603 - 708: taxonomic and phylogenetic notes on genera and species. Fungal Diversity 87: 1 - 235. http: // doi. org / 10.1007 / s 13225 - 017 - 0391 - 3","Bahl, J., Jeewon, R. & Hyde, K. D. (2005) Phylogeny of Rosellinia capetribulensis sp. nov. and its allies (Xylariaceae). Mycologia 97: 1102 - 1110. https: // doi. org / 10.3852 / mycologia. 97.5.1102","Daranagama, D. A., Camporesi, E., Tian, Q., Liu, X., Chamyuang, S., Stadler, M. & Hyde, K. D. (2015) Anthostomella is polyphyletic comprising several genera in Xylariaceae. Fungal Diversity 73: 203 - 238. http: // doi. org / 10.1007 / s 13225 - 015 - 0329 - 6","Dai, D. - Q., Phookamsak, R., Wijayawardene, N. N., Li, W. - J., Bhat, D. J., Xu, J. - C., Taylor, J. E., Hyde, K. D. & Chukeatirote, E. (2017) Bambusicolous fungi. Fungal Diversity 82: 1 - 105. https: // doi. org / 10.1007 / s 13225 - 016 - 0367 - 8","Hsieh, H. M., Ju, Y. M. & Rogers, J. D. (2005) Molecular phylogeny of Hypoxylon and closely related genera. Mycologia 97: 844 - 865. https: // doi. org / 10.3852 / mycologia. 97.4.844","Wendt, L., Sir, E. B., Kuhnert, E., Lambert, C., Hladki, A. I., Remero, A. I., Luangsa-Ard, J. J., Srikitikulchai, P., Persoh, D. & Stadler, M. (2018) Resurrection and emendation of the Hypoxylaceae, recognised from a multigene phylogeny of the Xylariales. Mycological Progress 17: 115 - 154. http: // doi. org / 10.1007 / s 11557 - 017 - 1311 - 3","Li, Q. - R., Wen, T. - C., Kang, J. - C. & Hyde, K. D. (2015 b) A new species of Collodiscula (Xylariaceae) from China. Phytotaxa 205: 187 - 196. http: // doi. org / 10.11646 / phytotaxa. 205.3.6","Li, Q. - R., Kang, J. - C. & Hyde, K. D. (2015 a) Two new species of the genus Collodiscula (Xylariaceae) from China. Mycological Progress 14: 52. http: // doi. org / 10.1007 / s 11557 - 015 - 1075 - 6","Jaklitsch, W. M. & Voglmayr, H. (2012) Phylogenetic relationships of five genera of Xylariales and Rosasphaeria gen. nov. (Hypocreales). Fungal Diversity 52: 75 - 98. http: // doi. org / 10.1007 / s 13225 - 011 - 0104 - 2","Xie, X., Liu, L. - L., Shen, X. - C., Kang, Y. - Q. & Li, Q. - R. (2020) Contributions to species of Xylariales in China - 3. Collodiscula tubulosa (Xylariaceae). Phytotaxa 428: 122 - 130. http: // doi. org / 10.11646 / phytotaxa. 428.2.6","Han, J. & Ma, J. (2005) Molecular and morphological investigation of the genus Daldinia in Northern Europe. Trace Elements Science 104: 275 - 280. https: // doi. org / 10.1017 / S 0953756299001719","Pelaez, F., Gonzalez, V., Platas, G. & Sanchez-Ballesteros, J. (2008) Molecular phylogenetic studies within the family Xylariaceae based on ribosomal DNA sequences. Fungal Diversity 31: 111 - 134.","Kuhnert, E., Fournier, J., Peroh, D., Luangsa-Ard, J. J. D. & Stadler, M. (2014) New Hypoxylon species from Martinique and new evidence on the molecular phylogeny of Hypoxylon based on ITS rDNA and β- tubulin data. Fungal Diversity 64: 181 - 203. http: // doi. org / 10.1007 / s 13225 - 013 - 0264 - 3","Stadler, M., Kuhnert, E., Persoh, D. & Fournier, J. (2013) The Xylariaceae as model example for a unified nomenclature following the \" one fungus-one name \" (1 F 1 N) concept. Mycology 4: 5 - 21.","Johnston, P. R., Rogers, J. D., Park, D. & Martin, N. A. (2016) Entalbostroma erumpens gen. et sp. nov. (Xylariaceae) from Phormium in New Zealand. Mycotaxon 131: 765 - 771. http: // doi. org / 10.5248 / 131.765","Senanayake, I. C., Maharachchikumbura, S. S. N., Hyde, K. D., Bhat, D. J., Gareth Jones, E. B., McKenzie, E. H. C., Dai, D. - Q., Daranagama, D. A., Dayarathne, M., Goonasekara, I., Konta, S., Li, W. - J., Shang, Q. - J., Stadler, M., Wijayawardene, N. N., Xiao, Y. - P., Norphanphoun, C., Li, Q. - R., Liu, X. - Z., Bahkali, A., Kang, J. - C., Wang, Y., Wen, T. - C., Wendt, L., Xu, J. - C. & Erio, C. (2015) Towards unraveling relationships in Xylariomycetidae (Sordariomycetes). Fungal Diversity 73: 73 - 144. http: // doi. org / 10.1007 / s 13225 - 015 - 0340 - y","Fournier, J., Flessa, F., Persoh, D. & Stadler, M. (2011) Three new Xylaria species from southwestern Europe. Mycological Progress 10: 33 - 52. http: // doi. org / 10.1007 / s 11557 - 010 - 0671 - 8","Sir, E. B., Lambert, C., Wendt, L., Hladki, A. I. & Stadler, M. (2016) A new species of Daldinia (Xylariaceae) from the Argentine subtropical montane forest. Mycosphere 7: 1378 - 1388. http: // doi. org / 10.5943 / mycosphere / 7 / 9 / 11","Hino, I. & Katumoto, K. (1955) Illustrationes fungorum bambusicolorum III. Bulletin of the Faculty of Agriculture, Yamaguchi University 6: 29 - 68."]}

Collodiscula japonica I. Hino & Katum., Bull. Faculty Agricult., Yamaguchi University 6: 55 (1955) (Fig. 3) ≡ Acanthodochium collodisculae Samuels, J.D. Rogers & Nagas., Mycotaxon 28(2): 457 (1987) MycoBank: MB295371 Saprobic on dead bamboo culms, arising from the center of the base and perpendicular to the surface of the substrate. Sexual morph: Stromata scattered, superficial, pulvinate, 0.8–1 mm diam., 0.3–0.6 mm high, containing 1(–3) ascomata, coronate with the outer stroma remaining as a ‘crown’ around the inner stroma, black, carbonaceous, the combined outer and inner stromal layers fused to form a single layer, easily stripped from the inner stroma. Perithecia semiglobose, 0.4–0.6 mm diam., 0.3–0.6 mm high. Asci 120–148 × 7.0–11.4 μm (mean 132 × 8.3 μm, n = 30), 8-spored, unitunicate, short-stipitate, apically rounded with a J+, funnel-shaped apical apparatus, blue staining in Melzer’s reagent. Ascospores 19–26 × 4.5–5.5 μm (mean 22.5 × 4.8 μm, n = 30), fusiform to narrowly fusiform, brown to dark brown, 1-septate, not or slightly constricted at septum, inaequilateral, with rounded ends, smooth- walled, lacking germ slits or appendages. Asexual morph: Acanthodochium collodisculae. Specimens examined: — CHINA. Guizhou Province: Tongren City, Fanjingshan Nature Reserve (27.533842°N, 108.454326°E), elev. 920 m, on dead bamboo culms, 10 October 2020, Q.R. Li 2020 FJS37 (GMB0035, KUN-HKAS 112692; living culture, GMBC0035). Culture characteristics:— Ascospores germinated on PDA within 24 hours at 25 °C, colonies, dense but thinning towards the edge, edge irregular, white from above, reverse similar in colour. No conidia were observed on PDA and OA media. Habitat/Distribution:— Known to inhabit dead bamboo, China, Japan, Russia. Other specimens examined:— CHINA. Guizhou Province: Tongren City, Fanjingshan Nature Reserve (27.544283°N, 108.42908°E), elev. 1037 m, on dead bamboo culms, 10 October 2020, Q.R. Li, collection number: 2020 FJS29 (GMB0034, KUN-HKAS 112690; living culture, GMBC0034). Notes:— The genus Collodiscula was introduced and typified by C. japonica from bamboo culms in Japan. Subsequently, C. japonica has been reported from Russia (Vasilyeva 1998), Taiwan (Ju & Rogers 1999), and Zhejiang province, China (Jaklitsch & Voglmayr 2012). Phylogenetic analyses of the combined ITS, RPB 2, β-tubulin and α-actin sequences dataset shows that our strains, GMB0034 and GMB0035, clade with C. japonica (CBS124266) with high support (95% ML, 0.98 BYPP; Fig. 1). The new collections are morphologically the same as C. japonica. Interestingly, all collections of C. japonica were found on the surface of bamboo culms., Published as part of Wu, You-Peng, Pi, Yin-Hui, Long, Si-Han, Lin, Yan, Long, Qing-De, Kang, Ji-Chuan, Kang, Ying-Qian, Shen, Xiang-Chun, Wijayawardene, Nalin N., Zhang, Xu & Li, Qi-Rui, 2021, Morphological and phylogenetic study of five species of Astrocystis and Collodiscula on bamboo, pp. 265-284 in Phytotaxa 522 (4) on page 273, DOI: 10.11646/phytotaxa.522.4.1, http://zenodo.org/record/5565846, {"references":["Vasilyeva, L. N. (1998) Plantae non Vasculares, Fungi et Bryopsidae Orientis extremi Rossica. Fungi. Tomus 4. Pyrenomycetidae et Loculoascomycetidae. Nauka, Petropoli, pp. 418.","Ju, Y. M. & Rogers, J. D. (1999) The Xylariaceae of Taiwan (excluding Anthostomella). Mycotaxon 73: 343 - 440.","Jaklitsch, W. M. & Voglmayr, H. (2012) Phylogenetic relationships of five genera of Xylariales and Rosasphaeria gen. nov. (Hypocreales). Fungal Diversity 52: 75 - 98. http: // doi. org / 10.1007 / s 13225 - 011 - 0104 - 2"]}

Changes in neurotransmitter receptor abundance at post-synaptic elements play a pivotal role in regulating synaptic strength. For this reason, there is significant interest in identifying and characterizing the scaffolds required for receptor localization at different synapses. Here we analyze the role of two C. elegans post-synaptic scaffolding proteins (LIN-2/CASK and FRM-3/FARP) at cholinergic neuromuscular junctions. Constitutive knockouts or muscle specific inactivation of lin-2 and frm-3 dramatically reduced spontaneous and evoked post-synaptic currents. These synaptic defects resulted from the decreased abundance of two classes of post-synaptic ionotropic acetylcholine receptors (ACR-16/CHRNA7 and levamisole-activated AChRs). LIN-2’s AChR scaffolding function is mediated by its SH3 and PDZ domains, which interact with AChRs and FRM-3/FARP, respectively. Thus, our findings show that post-synaptic LIN-2/FRM-3 complexes promote cholinergic synaptic transmission by recruiting AChRs to post-synaptic elements.

SUMMARYThe development of functional synapses in the nervous system is important for animal physiology and behaviors. The synaptic transmission efficacy can be modulated by the environment to accommodate external changes, which is crucial for animal reproduction and survival. However, the underlying plasticity of synaptic transmission remains poorly understood. Here we show that in C. elegans, the male pheromone increases the hermaphrodite cholinergic transmission at the neuromuscular junction (NMJ), which alters hermaphrodites’ locomotion velocity and mating efficiency in a developmental stage-dependent manner. Dissection of the sensory circuits reveals that the AWB chemosensory neurons sense those male pheromones and further transduce the information to NMJ using cGMP signaling. Exposure of hermaphrodites to male pheromones specifically increases the accumulation of presynaptic CaV2 calcium channels and clustering of postsynaptic receptors at cholinergic synapses of NMJ, which potentiates cholinergic synaptic transmission. Thus, our study demonstrates a circuit mechanism for synaptic modulation by sexual dimorphic pheromones.