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Understanding the response of biomass allocation in current-year twigs is crucial for elucidating the plant life-history strategies under heterogeneous volcanic habitats. We aimed to test whether twig biomass allocation, within-leaf biomass allocation, and the size-number trade-off of Betula platyphylla would be influenced. We measured twig traits of B. platyphylla in Wudalianchi volcanic kipuka, the lava platform, and Shankou lake in northeastern China using standardized major axis analyses. The results showed that the leaf number, total lamina mass (TLAM), stem mass (SM), and twig mass (TM) were significantly different between the three habitats and were greatest in kipuka with abundant soil nutrients. TLAM and SM scaled allometrically with respect to TM, while the normalization constants of the lava platform differ significantly between kipuka and Shankou lake, which showed that under certain TM, leaves gain more biomass in the lava platform. However, within the leaf, individual lamina mass (ILM) scaled isometrically with respect to individual petiole mass (IPM) in kipuka and the lava platform, but ILM scaled allometrically to IPM in Shankou lake. Our results indicated that inhabitats influenced the twig traits and biomass allocation and within-leaf biomass allocation are strategies for plants to adapt to volcanic heterogeneous habitats.

The relationship between the fungal community characteristics and soil environmental factors of volcanic ecosystem in Wudalianchi, China were investigated. The soil fungal community structure and diversity of new, old, and non-erupting volcanos were explored through highthroughput sequencing technology. The result showed that the physical and chemical properties of three plots were significantly different. Through sequencing 578 species, 366 genera, 202 families, 89 orders, 32 classes, and 11 phyla were detected. Among them Ascomycota and Basidiomycota were the dominant fungi phyla. The relative abundance of various flora determined by phylum classification showed significant differences. The Shannon, Simpson, Ace, and Chao1 indices for the soil fungi in the three plots were also significantly different. Redundancy and correlation analyses showed that the α diversity of fungi was significantly correlated with pH, organic matter and total nitrogen in the soil. These results indicate that soil environmental factors influence the fungal diversity in the different volcanic ecosystems in Wudalianchi, China. Bangladesh J. Bot. 50(2): 327-334, 2021 (June)

Background Some ferns have medicinal properties and are used in therapeutic interventions. However, the classification and phylogenetic relationships of ferns remain incompletely reported. Considering that chloroplast genomes provide ideal information for species identification and evolution, in this study, three unpublished and one published ferns were sequenced and compared with other ferns to obtain comprehensive information on their classification and evolution. Materials and Methods The complete chloroplast genomes of Dryopteris goeringiana (Kunze) Koidz, D. crassirhizoma Nakai, Athyrium brevifrons Nakai ex Kitagawa, and Polystichum tripteron (Kunze) Presl were sequenced using the Illumina HiSeq 4,000 platform. Simple sequence repeats (SSRs), nucleotide diversity analysis, and RNA editing were investigated in all four species. Genome comparison and inverted repeats (IR) boundary expansion and contraction analyses were also performed. The relationships among the ferns were studied by phylogenetic analysis based on the whole chloroplast genomes. Results The whole chloroplast genomes ranged from 148,539 to 151,341 bp in size and exhibited typical quadripartite structures. Ten highly variable loci with parsimony informative (Pi) values of > 0.02 were identified. A total of 75–108 SSRs were identified, and only six SSRs were present in all four ferns. The SSRs contained a higher number of A + T than G + C bases. C‐to‐U conversion was the most common type of RNA editing event. Genome comparison analysis revealed that single‐copy regions were more highly conserved than IR regions. IR boundary expansion and contraction varied among the four ferns. Phylogenetic analysis showed that species in the same genus tended to cluster together with and had relatively close relationships. Conclusion The results provide valuable information on fern chloroplast genomes that will be useful to identify and classify ferns, and study their phylogenetic relationships and evolution., Study reported three newly sequenced chloroplast genomes of ferns.Study provided more information on understanding evolution and phylogenetic of ferns.

Late onset Alzheimer's disease (LOAD) is a genetically complex and clinically heterogeneous disease. Recent large-scale genome wide association studies (GWAS) have identified more than twenty loci that modify risk for AD. Despite the identification of these loci, little progress has been made in identifying the functional variants that explain the association with AD risk. Thus, we sought to determine whether the novel LOAD GWAS single nucleotide polymorphisms (SNPs) alter expression of LOAD GWAS genes and whether expression of these genes is altered in AD brains. The majority of LOAD GWAS SNPs occur in gene dense regions under large linkage disequilibrium (LD) blocks, making it unclear which gene(s) are modified by the SNP. Thus, we tested for brain expression quantitative trait loci (eQTLs) between LOAD GWAS SNPs and SNPs in high LD with the LOAD GWAS SNPs in all of the genes within the GWAS loci. We found a significant eQTL between rs1476679 and PILRB and GATS, which occurs within the ZCWPW1 locus. PILRB and GATS expression levels, within the ZCWPW1 locus, were also associated with AD status. Rs7120548 was associated with MTCH2 expression, which occurs within the CELF1 locus. Additionally, expression of several genes within the CELF1 locus, including MTCH2, were highly correlated with one another and were associated with AD status. We further demonstrate that PILRB, as well as other genes within the GWAS loci, are most highly expressed in microglia. These findings together with the function of PILRB as a DAP12 receptor supports the critical role of microglia and neuroinflammation in AD risk.

Author(s): Chen, Zhanghua; Pereira, Mark A; Seielstad, Mark; Koh, Woon-Puay; Tai, E Shyong; Teo, Yik-Ying; Liu, Jianjun; Hsu, Chris; Wang, Renwei; Odegaard, Andrew O; Thyagarajan, Bharat; Koratkar, Revati; Yuan, Jian-Min; Gross, Myron D; Stram, Daniel O | Abstract: BackgroundGenome-wide association studies (GWAS) have identified genetic factors in type 2 diabetes (T2D), mostly among individuals of European ancestry. We tested whether previously identified T2D-associated single nucleotide polymorphisms (SNPs) replicate and whether SNPs in regions near known T2D SNPs were associated with T2D within the Singapore Chinese Health Study.Methods2338 cases and 2339 T2D controls from the Singapore Chinese Health Study were genotyped for 507,509 SNPs. Imputation extended the genotyped SNPs to 7,514,461 with high estimated certainty (r(2)g0.8). Replication of known index SNP associations in T2D was attempted. Risk scores were computed as the sum of index risk alleles. SNPs in regions ± 100 kb around each index were tested for associations with T2D in conditional fine-mapping analysis.ResultsOf 69 index SNPs, 20 were genotyped directly and genotypes at 35 others were well imputed. Among the 55 SNPs with data, disease associations were replicated (at pl0.05) for 15 SNPs, while 32 more were directionally consistent with previous reports. Risk score was a significant predictor with a 2.03 fold higher risk CI (1.69-2.44) of T2D comparing the highest to lowest quintile of risk allele burden (p = 5.72 × 10(-14)). Two improved SNPs around index rs10923931 and 5 new candidate SNPs around indices rs10965250 and rs1111875 passed simple Bonferroni corrections for significance in conditional analysis. Nonetheless, only a small fraction (2.3% on the disease liability scale) of T2D burden in Singapore is explained by these SNPs.ConclusionsWhile diabetes risk in Singapore Chinese involves genetic variants, most disease risk remains unexplained. Further genetic work is ongoing in the Singapore Chinese population to identify unique common variants not already seen in earlier studies. However rapid increases in T2D risk have occurred in recent decades in this population, indicating that dynamic environmental influences and possibly gene by environment interactions complicate the genetic architecture of this disease.