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The origin of Precambrian dolomites has attracted research interest as a result of their association with petroleum resources. The long diagenetic history of these dolomites and multiple periods of hydrothermal activity mean that dating and identifying different periods of dolomite formation is challenging. This study focuses on dolomites in the Precambrian Dengying Formation of the Sichuan Basin, central China, and presents new petrographic, in situ laser ablation inductively coupled plasma mass spectrometry U–Pb and trace element, and Sr–C–O isotopic data to characterize three types of dolomite and constrain their age and origin. In situ U–Pb dating of type I dolomite yielded a lower intercept age of 637 ± 35 Ma. The rare earth element (REE) patterns, 87Sr/86Sr ratios (0.70827–0.70903), and δ13C VPDB (0.8‰–1.0‰) and δ18O VPDB (−1.5‰ to −1.0‰) values of type I dolomite indicate their derivation from seawater or a precursory source with seawater characteristics. Type II dolomite yielded an age of 636 ± 15 Ma and has lower ΣREE and slightly higher δ13C VPDB (1.2‰–1.5‰) and δ18O VPDB (−0.9‰ to −0.3‰) values than type I, as well as similar 87Sr/86Sr ratios and parallel REE patterns that are indicative of formation by reflux seepage dolomitization. The type III dolomite is characterized by large crystals, unique REE patterns, high 87Sr/86Sr values (0.70942–0.70975), and negative δ18O VPDB values (−6.4‰ to −3.1‰) that indicate a hydrothermal origin. The relationships between hydrothermal dolomite and bitumen indicate that the paleo-oil charging within the Dengying Formation reservoir occurred after the hydrothermal activity at 516 ± 49 Ma. The early hydrothermal activity provided space for the subsequent fluid movement, and oil and gas charging. Our integrated approach, incorporating petrographic, geochemical, isotopic, and geochronological data, constrains the ages of different dolomite phases and an oil-charging event within the Dengying Formation reservoir and provides new insights into the evolution of petroleum systems in general. • We identified three types of dolomites of Dengying Formation matching with the age of diagenesis and fluid activity. • The LA–ICP–MS in situ U–Pb dating of Dengying Formation dolomite yields a lower intercept age of 637 ± 35 Ma. • The dating results suggest an extensional event existed at 516 ± 49 Ma, and accounted for the deposition of hydrocarbon source rocks. • This study outlines potential approaches for furthering our understanding of dolomites and ancient petroleum systems. [ABSTRACT FROM AUTHOR]

• gma-miR169c is widely expressed in soybean tissues and induced by polyethylene glycol, high salt levels, cold stress and abscisic acid. • Arabidopsis overexpressing gma-miR169c is more sensitive to drought stress, with reduced survival, accelerated leaf water loss, and shorter root length than the wild-type plants. • gma-miR169c negatively regulates the drought stress response by inhibiting the expression of the targets AtNFYA1 and AtNFYA5 and reducing the transcript levels of the stress response genes AtRD29A , AtRD22 , AtGSTU25 and AtCOR15A. The miR169 family, a large-scale microRNA gene family conserved in plants, is involved in stress responses, although how soybean miR169 functions in response to drought stress remains unclear. We show that gma-miR169c exerts a negative regulatory role in the response to drought stress by inhibiting the expression of its target gene, nuclear factor Y–A (NF-YA). A real-time RT-PCR analysis indicated that gma-miR169c is widely expressed in soybean tissues and induced by polyethylene glycol (PEG), high salt, cold stress and abscisic acid (ABA). Histochemical ß-glucuronidase (GUS) staining showed that the gma-miR169c promoter drives GUS reporter gene expression in various transgenic Arabidopsis tissues, and the stress-induced pattern was confirmed in transgenic Arabidopsis and transgenic soybean hairy roots. Arabidopsis overexpressing gma-miR169c is more sensitive to drought stress, with reduced survival, accelerated leaf water loss, and shorter root length than wild-type plants. We identified a precise cleavage site for 10 gma-miR169c targets and found reduced transcript levels of the AtNFYA1 and AtNFYA5 transcription factors in gma-miR169c -overexpressing Arabidopsis and reduced expression of the stress response genes AtRD29A , AtRD22 , AtGSTU25 and AtCOR15A. These results indicate that gma-miR169c plays a negative regulatory role in drought stress and is a candidate miRNA for improving plant drought adaptation. [ABSTRACT FROM AUTHOR]

• A distinct oil group was discovered in the Dongying Depression. • Related source rock of the distinct oil group has abundant bacteria/algae inputs. • Norcholestanes and triaromatic steroids are effectively used in oil classification. • This oil group has a higher abundance of nordiacholestanes than norcholestanes. • This oil group contains extremely high abundances of 4-methyltriaromatic steroids. The lower third and upper fourth members of the Eocene Shahejie Formation (lower Es3 and upper Es4) are known as two sets of effective source rocks in the Dongying Depression, Bohai Bay Basin. In this study, the saturated and aromatic steroids of 20 crude oil samples from the Dongying Depression were systematically investigated using gas chromatography–mass spectrometry (GC–MS) and GC–MS metastable reaction monitoring. Based on the distribution patterns of the steranes, norcholestanes, and triaromatic steroids, the Group I and II oils were clearly identified and shown to be derived from the lower Es3 and upper Es4 source rocks, respectively. Significantly, it was discovered that three oil samples collected from the Eocene Kongdian Formation and the Ordovician reservoirs exhibit completely different steroid and isotopic compositions from those of the Group I and II oils. These oils, as a distinct oil group (Group III), have the characteristics of abnormally high concentrations of C 29 steranes, 24-nordiacholestane, 27-nordiacholestane, C 28 triaromatic steroids, C 27 4α-methyltriaromatic steroids, and C 29 4α-methyl-24-ethyltriaromatic steroids, and low concentrations of 24-norcholestane, 27-norcholestane and triaromatic dinosteroids, and 13C depletion. Although the related source rock of Group III oils needs to be further clarified in the study area, the 13C depletion, abundant C 29 steranes, and low 24-norcholestane content may suggest greater bacteria/algae inputs (e.g., green algae rather than dinoflagellates) than both the lower Es3 and upper Es4 source rocks. Identification of the Group III oils indicates that the norcholestanes and triaromatic steroids may be more effective molecular fossils for the classification of crude oils in complicated petroleum exploration fields. [ABSTRACT FROM AUTHOR]

• The cotton cytoplasmic subgroup gene GhHSP70-26 is transcribed in response to polyethylene glycol and abscisic acid treatment and salt, cold, and heat stress. • Overexpression of the GhHSP70-26 gene in tobacco and silencing of the GhHSP70-26 gene in cotton showed that the GhHSP70-26 gene can improve plant tolerance to drought stress. • GhbZIP43 and GhHSF8 bind to cis -acting ABREs and HSEs, respectively, to regulate the transcription of GhHSP70-26 , and the GhHSP70-26 protein interacts with the GhAPX2 protein. The 70-kDa heat shock protein (HSP70) is a molecular chaperone that plays an important role in the response of plants to abiotic stress, but the function and molecular mechanism of HSP70 in the cotton drought stress response are unclear. In this study, the HSP70-encoding gene GhHSP70-26 , which belongs to the cytoplasmic HSP70 subgroup, was cloned from upland cotton (Gossypium hirsutum L.). The transcript level of GhHSP70-26 in cotton leaves was higher than that in cotton stems and roots. GhHSP70-26 was found to respond at the transcriptional level to polyethylene glycol (PEG) and abscisic acid (ABA) treatment and to cold, salt, and heat stress, and its transcript level was positively correlated with the drought resistance of different cotton varieties. Heterologous overexpression of the GhHSP70-26 gene improved the drought resistance of transgenic tobacco compared with that of wild-type (WT) tobacco, and the transgenic tobacco plants were characterized by low leaf wilting, high survival, low leaf water loss, increased root length and high chlorophyll content. Moreover, the transgenic tobacco plants overexpressing GhHSP70-26 had higher proline contents, higher superoxide dismutase (SOD) and peroxidase (POD) enzyme activities, and lower malondialdehyde (MDA) and reactive oxygen species (ROS) contents than the WT tobacco plants. The transcript levels of the stress response-related genes NtLEA , NtERD10D , NtPOD , NtSOD , and NtNCED3-1 in transgenic tobacco overexpressing GhHSP70-26 were significantly higher than those in WT tobacco. In contrast, under drought stress, unlike the results obtained with the pTRV2 empty vector (EV)-transformed and WT cotton plants, the use of virus-induced gene silencing (VIGS) technology to silence the GhHSP70-26 gene in cotton resulted in plants with severely wilted leaves, an increased water loss rate, a higher MDA content, and higher relative electrical conductivity (REC). Furthermore, yeast one-hybrid assays showed that GhbZIP43 and GhHSF8 bind to ABA-responsive elements (ABREs) and heat shock elements (HSEs) in the GhHSP70-26 promoter, respectively. Moreover, yeast two-hybrid, bimolecular fluorescence complementation and luciferase complementation assays showed that the GhHSP70-26 protein interacts with the ascorbate peroxidase (APX) GhAPX2 protein. These results indicate that by reducing the degrees of cell membrane damage and cellular damage caused by ROS stress, the GhHSP70-26 protein plays a positive role in the response of plants to drought stress. [ABSTRACT FROM AUTHOR]

Free oils and inclusion oils were extracted from the third member of the Eocene Shahejie Formation (Es3) reservoir sandstones of the wells Chun 51 and Liang 28 in the Dongying Depression, China, and then analyzed by gas chromatography–mass spectrometry (GC–MS). Results show that biomarker distribution characteristics of the free oils and their associated inclusion oils are similar in each Es3 reservoir sandstones of the two wells, but the distributions of Pr/Ph ratio, gammacerane, hopane series and C 27 –C 29 steranes in well Chun 51 oils are strikingly different from those of well Liang 28 oils. However, the C 29 sterane ββ/(ββ + αα), Ts/(Ts + Tm) and C 31 hopane 22S/(22S + 22R) ratios of inclusion oils are higher than those of related free oils in all the samples, this may indicate that maturity indicators decreased after reaching the maximum and relatively high mature oils were trapped in petroleum inclusions. Comparison with biomarkers of source-rock extracts shows that oils in the Es3 reservoir of well Chun 51 were generated from the upper Es4 source rocks, whereas oils in the Es3 reservoir of well Liang 28 were derived from the lower Es3 source rocks. Moreover, the microthermometric data and burial history indicate one oil-charging episode in the Es3 reservoirs of the two wells, during the late Neogene. It's concluded that different charging histories of these two reservoirs were attributed mainly to the sealing effect of the fault. • Biomarker compositions of fluid inclusions and free oils were discussed. • Oil-sources of the two studied Es3 reservoirs were single but different. • Oil-charging times of the two Es3 reservoirs were defined. • Different oil-charging histories of the two Es3 reservoirs were analyzed. [ABSTRACT FROM AUTHOR]

Highlights • Unique geochemistry of high mature reservoir pyrobitumens in Lower Cambrian. • Parallel application and cross-validation of REE, carbon isotopes and biomarkers. • Multiproxy study of oceanographic conditions in the Lower Cambrian. • Variations of inorganic element ratios in probitumens along migration pathways. • A potential means through analysis of bitumen to study paleo-oil reservoirs. Abstract The Moxi–Gaoshiti Bulge of the Sichuan Basin in southwestern China is unique because it provides insights into the geochemistry of Lower Cambrian reservoir bitumens and their geological significance for paleo-oil reservoirs. Analyses of biomarkers, carbon isotopes, trace elements (TE) and rare earth elements (REE) were conducted on reservoir bitumens and the associated source rocks to constrain sedimentary environments and bitumen/paleo-oil sources. Based on biomarkers, carbon isotopes, TE ratios and REE distribution patterns, both of the Cambrian Qiongzhisi (Є 1 q) and Sinian Dengying (Z 2 dn) source rocks can be hydrocarbon sources for the Cambrian Longwangmiao (Є 1 l) bitumens in the MG Bulge (Lower Cambrian Doushantuo Formation not discussed here). Abundant n -alkanes relative to isoprenoids, significant C 21 and C 22 steranes, predominance of dibenzothiophene (DBT), and low ratios of biomarkers, such as Pr/Ph, DBT/P, C 22 TT/C 21 TT and C 35 H(22S)/C 34 H(22S) indicated that the source rock was characterized as shale from an overall highly reducing marine depositional environment. The average δ13C values from the compositions of the solid bitumens show an abnormal order: saturate hydrocarbons < asphaltenes < N-S-O compounds < aromatic hydrocarbons, suggesting that high temperature might affect the normal fractionation among different organic matter fractions. The reservoir bitumens are enriched in Mo, Tl, Pb and Ba, strongly depleted in Bi Compared to PAAS, and mostly well correlated in the REE distribution patterns. In the primary migration pathways suggested by the DBT concentration, the parameters ∑REE and Zr/Cu show an overall increase, and the ratios V/Ni, Ni/Co, V/Zr and V/Cr have decreasing trends. The comprehensive analyses of molecular biomarkers, carbon isotopes, TE and REE in pyrobitumens of the highly mature reservoirs in this study suggest a potential means to study paleo-oil reservoirs, and can thus provide valuable information for deep oil and gas exploration in Precambrian – Lower Cambrian petroleum systems. [ABSTRACT FROM AUTHOR]

The Moxi–Gaoshiti (MG) Bulge of the Sichuan Basin in southwestern China is unique because of its enormous gas field in old Cambrian and Proterozoic marine strata, where oils in carbonate reservoirs have been nearly completely cracked to solid bitumen and natural gas because of high to post-mature thermal maturity levels. Numerous solid bitumen-bearing dolomites obtained from boreholes in the MG Bulge provide an ideal opportunity to trace the major filling orientations for the Lower Cambrian paleo-oil reservoirs. Biomarker analysis was conducted on solid bitumens through quantitative detection with gas chromatography–mass spectrometry. Results show that all solid bitumen samples in the MG Bulge exhibit similar compositions of molecular markers, thereby implying that they belong to the same oil population and that paleo-oils should be derived from the same source kitchen/bed. Low pristane/phytane and dibenzothiophene (DBT)/phenanthrene ratios, as well as the predominance of DBT among DBT, dibenzofuran, and fluorene, are observed in the solid bitumen samples, which suggest that related paleo-oil reservoirs likely originated from a highly reducing marine shale environment. All isopleth maps of the DBT concentrations, 4-methylDBT/1-methylDBT, 4,6-dimethylDBT/(1,4 + 1,6)-dimethylDBT (DMDBT), and (2,6 + 3,6)-DMDBT/(1,4 + 1,6)-DMDBT ratios consistently indicate that the overall orientation of oil migration in the MG Bulge is primarily from the west-to-east direction, with the strongest filling point located at approximately the Mx12 well. The north-to-west direction is an additional filling orientation. These indicators show that those paleo-oils that had been cracked to pyrobitumens mainly originated from a source kitchen in the western part of the MG Bulge. A hydrocarbon source kitchen in the northern part of the MG Bulge may also have developed but further research on this is needed. The recognition of these solid bitumen molecular signatures, particularly the consistent results using DBT concentrations and alkyl DBT thermal maturity indicators, suggests a potential approach that can be applied to the study of paleo-oil reservoirs. [ABSTRACT FROM AUTHOR]

The geochemistry, origin and charge history of oils from the Yuqi area of Tarim Basin have been investigated, through GC, GC-MS and fluid inclusion microthermometry analysis. The Yuqi oils accumulated mainly in three intervals: (1) in the Lower-Middle Ordovician Yingshan Formation (O 1-2 y ) carbonate reservoirs; (2) in the overlying Upper Triassic Halahatang Formation (T 3 h ); and (3) in the Lower Cretaceous Yageliemu Formation (K 1 y ) sandstones. Oils from different reservoirs have distinct physical properties, varying from extra-heavy (O 1-2 y), heavy (T 3 h ), to light oils (T 3 h and K 1 y ). However, their geochemical compositions show a high degree of similarity, which indicates that they derive from the same source rock. Abundant tricyclic terpanes, gammacerane, dibenzothiophene and C 21 C 22 steranes, together with a low level of diasteranes, indicate an anoxic marine source rock for oils in the Yuqi area. Oil-oil correlation shows that Yuqi oils derive from the same source bed as Tahe oils. The co-occurrence of intact n -alkanes and 25-norhopanes in all the samples supports the proposition that there is a mixture of an early filled severely biodegraded oil and a late filled fresh oil. In this study, charge history is examined on the basis of integration of fluid inclusion homogenization temperature data with 1D burial-thermal history models. Two episodes of oil charging are identified in the O 1-2 y reservoir (well YQX1-1) at around 436-420 Ma (Middle-Late Silurian) and 10-3 Ma (Miocene to Pliocene), respectively. For the samples from the T 3 h and K 1 y intervals, only one episode of oil charge is indicated by the homogenization temperatures of coexisting aqueous inclusions with an inferred timing around 10-3 Ma. The T 3 h heavy oil reservoir is assumed to be a secondary hydrocarbon pool, which accumulated by re-migration and re-distribution of hydrocarbons from O 1-2 y hydrocarbon pools. The few early biodegraded oils in the K 1 y light oils were probably picked up along the migration pathway during the late fresh oil charging. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) have important functions in the plant salt stress response. However, the functions of nonconserved miRNAs in soybean salt stress adaptation remain unclear. In this study, the soybean nonconserved miRNA gma-miR4359b and its target mRNA F-box gene GmFBX193 were functionally identified in response to salt stress. gma-miR4359b responded to salt stress in soybean hairy roots, stems, and leaves. Under salt stress, the root length ratio, root surface area ratio, root volume ratio, root tip number, survival rate, chlorophyll content, soluble sugar content, proline content, superoxide dismutase activity, and peroxidase enzyme activity of soybean hairy roots overexpressing gma-miR4359b (MIR4359b) were increased compared to those of the K599 (control) soybean hairy roots, while the relative electrolyte leakage and malondialdehyde content of the MIR4359b soybean hairy roots decreased. In contrast, soybean hairy roots in which target mimicry (MIM4359b) and short tandem target mimic (STTM4359b) inhibited gma-miR4359b exhibited a salt-sensitive phenotype. The transcription level of GmFBX193 was decreased in MIR4359b soybean hairy roots, while the transcription level of GmFBX193 was increased in MIM4359b and STTM4359b soybean hairy roots. GmFBX193 responded to salt stress in soybean roots, and GmFBX193 was identified as a nuclear-localized protein. Under salt stress, soybean hairy roots overexpressing GmFBX193 had a similar phenotype to MIM4359b and STTM4359b soybean hairy roots. Compared with K599 (control) soybean hairy roots, MIR4359b soybean hairy roots had 172 differentially expressed genes (DEGs), and MIM4359b soybean hairy roots had 2129 DEGs. Some known stress-related transcription factors were included among the DEGs. Taken together, these results suggest that gma-miR4359b plays a positive role in the soybean salt stress response by negatively regulating GmFBX193. • The nonconserved soybean miRNA gma-miR4359b and its target mRNA F-box gene GmFBX193 responded to salt stress. gma-miR4359b positively regulates the soybean response to salt stress by targeting GmFBX193. • gma-miR4359b is a positive regulator of salt tolerance in soybean. • GmFBX193 negatively regulates soybean tolerance to salt stress. • Transcriptome sequencing showed that gma-miR4359b could affect the transcription levels of some transcription factors related to the salt stress response. [ABSTRACT FROM AUTHOR]

Variations in biomarker concentrations, including tricyclic terpanes, tetracyclic terpanes, pentacyclic triterpanes, steranes, methylphenanthrenes and triaromatic steranes, were investigated at two different pressures (0.1 and 20 MPa) in multiple laboratory simulation experiments of oil-to-gas cracking. The low-maturity non-marine oil samples used in the study are from the Paleogene Shahejie Formation in the Dongying Depression, Bohai Bay Basin, eastern China. The oils were pyrolyzed to gas at elevated temperatures (300–650 °C) in an autoclave. The oil residue was sampled and analyzed at 50 °C temperature intervals. The results show that changes in biomarker concentrations are controlled mainly by temperature, while high pressures exert non-linear suppression effects on these variations. There appear to be different evolution regimes based on biomarker cracking and generation rates in the primary (400–500 °C for 0.1 MPa and 450–550 °C for 20 MPa) and secondary (500–650 °C for 0.1 MPa and 550–650 °C for 20 MPa) oil-to-gas cracking stages. Generally, the biomarker ratio differences are considerable in the early primary oil-to-gas cracking stage but decrease substantially in the later primary oil-to-gas cracking stage. The differences remain stable at high temperatures in the secondary oil-to-gas cracking stage. These oil-to-gas pyrolysis experiments reveal the characteristics of biomarker ratios, which are quite different from their distribution within the conventional “liquid window” at moderate maturity level. They provide new insights on oil biomarker maturity parameters under high temperatures and the change of oil and gas in deep buried basins. [ABSTRACT FROM AUTHOR]

TCP transcription factors play important regulatory roles in plant growth and development; however, their function in response to salt and drought stress in sea-island cotton (Gossypium barbadense) is unknown. Here, GbTCP4 expression was induced by abscisic acid (ABA), drought, and NaCl treatments. Under drought stress, compared to wild-type (WT) Arabidopsis , transgenic GbTCP4 -overexpressing Arabidopsis showed increased seed germination rate, root length and survival rate; additionally, it was ABA-insensitive at the germination stage but ABA-sensitive at the seedling stage, showing reduced stomatal opening and ABA enrichment. Under salt stress, compared to WT Arabidopsis , transgenic GbTCP4- overexpressing Arabidopsis showed greater root length, survival rate, and SPAD value and lower malondialdehyde (MDA) content. Conversely, under drought or salt stress, virus-induced gene-silenced GbTCP4 cotton showed decreased root length, area and volume and increased MDA content and sensitivity to drought and salt stress compared with control cotton. RNA-seq and quantitative real-time PCR analyses showed that GbTCP4 affected the transcription levels of genes across multiple abiotic stress-related metabolic pathways. Furthermore, GbTCP4 activated the transcription of GbUVR8 and GbbHLH130 by binding to their promoters. These results suggest that GbTCP4 positively regulates drought and salt stress responses and is a suitable candidate gene for improving plant drought and salt tolerance. • The sea-island cotton class II TCP gene GbTCP4 is induced by drought, salt, and ABA treatments. • Overexpression of GbTCP4 in Arabidopsis and silencing of GbTCP4 in cotton indicated that GbTCP4 is a positive regulator of drought and salt stress. • GbTCP4 regulates abiotic stress responses in an ABA-dependent manner. • The GbTCP4 transcription factor can affect the expression of key genes in multiple stress-related metabolic pathways. [ABSTRACT FROM AUTHOR]

The Ordovician reservoir in the Halahatang Depression is one of the most commercially prolific oil reservoirs in the Tabei Uplift of the Tarim Basin, NW China. For this study, a total of 94 oil samples were collected from 88 exploration/production wells in this oilfield. All of the oils possess similar organic molecular compositions and belong to the same oil population. Oil-to-source correlation results indicate that oil accumulations discovered in Halahatang Oilfield were derived from the Upper Ordovician source rocks. The homogenization temperatures of fluid inclusion in the Ordovician reservoir in the Halahatang Oilfield range from 90 °C to 100 °C and from 140 °C to 160 °C. The bimodal distribution pattern shown in a histogram of the homogenization temperatures indicates that the Ordovician oil reservoir in the Halahatang Oilfield has been charged twice. Coupling this information with the reconstructed burial and geothermal histories by 1-D basin modeling, the homogenization temperatures can be related to the relative geological ages of 419 Ma to 410 Ma and 16 Ma to 8 Ma, namely, the Middle to Late Silurian and the Middle Miocene respectively, representing the two phases of oil charging and entrapment. The oil migration orientation and charging pathways can be traced using molecular indicators, such as Ts/(Ts + Tm) and TMNr parameters. The overall oil migration orientation in the oilfield is generally from south to north. Therefore, the source kitchen for the Halahatang Oilfield is predicted to be to the south side of the depression. The southern part of the Halahatang Depression, along the oil charging pathways, is identified as the most promising region for oil exploration. [ABSTRACT FROM AUTHOR]

Determining the place of paleo-oil cracking is crucial to understanding the formation mechanism of the gas reservoirs in the Precambrian–Cambrian strata. For the old strata the attainable information is limited because most paleo-oil have been cracked to gas at high thermal maturity, such as the Anyue giant gas field in the Moxi–Gaoshiti Bulge of Sichuan Basin, Southwestern China. In this study, the place of paleo-oil cracking was discussed based on solid bitumen found in the reservoirs. Numerous solid bitumen from the deep boreholes in the Precambrian Dengying (Z 2 dn 2 and Z 2 dn 4 ) and Lower Cambrian Longwangmiao (Є 1 l) formations of the Moxi–Gaoshiti Bulge were analyzed. Elemental and carbon isotope analyses and optical microscopic observations, such as Raman spectroscopy, scanning electron microscopy, and electronic probe, were performed on these solid bitumen samples. The obtained parameters, including the reflectance of the solid bitumen, parameters I(D)/I(G) and S(D)/S(G) from the Raman spectra, the compositions and carbon isotope of gas, burial history, and the predicted "equivalent vitrinite reflectance Ro" (EqVRo) for reservoirs, jointly support that solid bitumen are epigenetic bitumen in reservoirs other than primary bitumen in source rocks. This study provides a relatively solid evidence of in situ cracking of paleo-oil and the thermochemical sulfate reduction reaction between paleo-oil and dolomite reservoirs. Pyrite were found both in carbonate rocks and argillaceous rock, and the sulfur in pyrite is perceived as a pathway of H 2 S formation. The results provide a basis for understanding the formation mechanism of the deep huge gas field that was derived from paleo-oil cracking, and may contribute to future petroleum exploration in deep Precambrian–Lower Cambrian systems. • A vitrinite reflectance profile of the extensive shale form one well was provided. • The solid bitumen was confirmed to be from in situ oil cracking at high thermal maturity. • Evidences proved that the TSR reaction was involved in this crude oil cracking. • The reaction of pyrite with hydrocarbons was considered as a pathway of H 2 S formation. • Maturities" of solid bitumen and reservoirs were quantitative calculated and compared. [ABSTRACT FROM AUTHOR]

• The GmNF-YA10 gene encodes an NF-YA transcription factor located in the nucleus that responds to PEG and ABA treatment at the transcription level. • Overexpression of the GmNF-YA10 gene increases the drought resistance of transgenic Arabidopsis by accumulating osmotic substances, slowing membrane lipid peroxidation, enhancing photosynthesis, regulating ABA-mediated stomatal closure, reducing the leaf water loss rate, and affecting the transcript levels of stress-related genes. • GmNF-YA10 gene participates in Arabidopsis response to drought stress through two pathways, ABA-dependent and ABA-independent. Nuclear factor (NF)-Y is composed of three subunits, NF-YA, NF-YB and NF-YC, and plays important roles in the regulation of plant abiotic stress response gene expression. However, the function of individual soybean NF-YA proteins in response to drought stress is unclear. In this study, the soybean NF-YA subunit gene GmNF-YA10 was cloned, and its function in response to drought stress was identified. GmNF-YA10 is broadly expressed in soybean tissues and is specifically located in the nucleus. In soybean roots, the transcription level of the GmNF-YA10 gene was induced by polyethylene glycol (PEG)-simulated drought stress and abscisic acid (ABA) treatment. Under mannitol stress, the germination rate of transgenic Arabidopsis overexpressing GmNF-YA10 was higher than that of wild-type (WT) Arabidopsis. After drought stress, the survival rate, relative water content, ABA content, proline content and chlorophyll content of transgenic Arabidopsis overexpressing GmNF-YA10 were higher than those of WT Arabidopsis while the rate of water loss and the contents of malondialdehyde and sucrose were lower than those of WT Arabidopsis , indicating that transgenic Arabidopsis overexpressing GmNF-YA10 has better drought resistance than WT Arabidopsis. Under the ABA treatment, the root length of transgenic Arabidopsis overexpressing GmNF-YA10 was shorter than that of WT Arabidopsis and the degree of stomatal closure was greater than that of WT Arabidopsis , indicating that transgenic Arabidopsis overexpressing GmNF-YA10 was more sensitive to ABA at the post-germination stage. Transcriptome sequencing and real-time quantitative PCR analysis showed that GmNF-YA10 affected the expression of both ABA-dependent and ABA-independent signalling pathway genes. These results indicate that GmNF-YA10 significantly improves the drought resistance of transgenic Arabidopsis through ABA-dependent and ABA-independent signal transduction pathways. [ABSTRACT FROM AUTHOR]

• The GbTCP5 gene encodes a sea-island cotton class II TCP CIN subclass transcription factor. • The GbTCP5 transcription factor is located in the nucleus, has transcriptional activation activity, and can bind to TCP II cis -acting elements. • Heterologous overexpression of the GbTCP5 gene increased root hair length, root hair and stem trichome density, and stem lignin content in transgenic Arabidopsis. • GbTCP5 binds the promoters of the GL3 , EGL3 , CPC , MYB46 , LBD30 , CesA4 , VND7 , CCOMT1 , and CAD5 genes to upregulate their expression. Teosinte branched1/cycloidea/proliferating cell factor1 (TCP) is a plant-specific protein family member involved in plant growth and development. However, the functions of most members of the cotton TCP family are unknown. In this study, the GbTCP5 gene encodes a sea-island cotton class II TCP CIN subclass transcription factor. The GbTCP5 transcription factor is located in the nucleus, has transcriptional activation activity, and can bind to TCP II cis -acting elements. GbTCP5 was widely expressed in tissues with the highest transcript level in the calyx. GbTCP5 is expressed at different developmental stages of the fiber and has significantly high transcriptional level expression in the fibers at 20, 30 and 35 days post anthesis (DPA). Heterologous overexpression of the GbTCP5 gene increased root hair length, root hair and stem trichome density, and stem lignin content in transgenic Arabidopsis compared to the wild type (WT). GbTCP5 binds the promoters of the GL3 , EGL3 , CPC , MYB46 , LBD30 , CesA4 , VND7 , CCOMT1 , and CAD5 genes to upregulate their expression. Moreover, the homologous genes of these genes are expressed in the fibers of different developmental stages of the sea-island cotton fiber. These results indicate that GbTCP5 regulates root hair development and secondary wall formation in Arabidopsis and may be a candidate gene for improving cotton fiber quality. [ABSTRACT FROM AUTHOR]

• GmFBX176 encodes a nuclear-localized F-box protein that responds to PEG treatment, ABA treatment, and salt stress at the transcriptional level. • Stress tolerance analysis of heterologous GmFBX176-overexpressing Arabidopsis revealed that GmFBX176 is a negative regulatory protein that improves tolerance to drought and salt stress. • GmFBX176-overexpressing Arabidopsis displayed reduced sensitivity to ABA. • Constitutive heterologous overexpression of the GmFBX176 gene affects stress-related physiological indicators and the transcript levels of stress response genes in transgenic Arabidopsis. As key components of the E3 ubiquitin ligase in the Skp1/Cullin or CDC53/F-box (SCF) complex, F-box proteins are involved in plant abiotic stress responses. However, the functions of F-box proteins in soybean in response to abiotic stress remain unclear. In this study, the soybean F-box protein-encoding gene GmFBX176 was cloned and functionally analyzed. GmFBX176 localized to the nucleus, was widely expressed in tissues (with the highest level in the roots), and responded to polyethylene glycol (PEG) treatment, abscisic acid (ABA) treatment, and salt stress at the transcriptional level. GmFBX176 -overexpressing Arabidopsis had lower survival rates; faster water loss rates; lower proline, sucrose and chlorophyll contents; greater malondialdehyde (MDA) contents; greater relative electrical conductivity (REC); and greater drought stress sensitivity than did wild-type (WT) Arabidopsis. Moreover, GmFBX176 -overexpressing Arabidopsis had lower survival rates, lower chlorophyll content, lower superoxide dismutase (SOD) activity, greater sensitivity to salt stress, longer roots, greater stomatal opening rates, and lower sensitivity to ABA than did WT Arabidopsis. Transcriptome sequencing and quantitative real-time PCR (qPCR) analyses revealed that GmFBX176 affects the transcript levels of stress response genes. These results indicate that GmFBX176 regulates ABA-mediated responses to drought and salt stress. [ABSTRACT FROM AUTHOR]