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Mangrove sediments host a diverse array of microbial populations and are characterized by high heterogeneity along their vertical depths. However, the genetic diversity within these populations is largely unknown, hindering our understanding of their adaptive evolution across the sediment depths. To elucidate their genetic diversity, we utilized metagenome sequencing to identify 16 high‐frequency microbial populations comprised of two archaea and 14 bacteria from mangrove sediment cores (0–100 cm, with 10 depths) in Qi'ao Island, China. Our analysis of the genome‐wide genetic variation revealed extensive nucleotide diversity in the microbial populations. The genes involved in the transport and the energy metabolism displayed a high nucleotide diversity (HND; 0.0045–0.0195; an indicator of shared minor alleles with the microbial populations). By tracking the processes of homologous recombination, we found that each microbial population was subjected to different purification selection levels at different depths (44.12% genes). This selection resulted in significant differences in synonymous/non‐synonymous mutation ratio between 0–20 and 20–100 cm layers, indicating the adaptive evolutionary process of microbial populations. Furthermore, our assessment of differentiation in the allele frequencies between these two layers showed that the functional genes involved in the metabolic processes of amino acids or cofactors were highly differential in more than half of them. Together, we showed that the nucleotide diversity of microbial populations was shaped by homologous recombination and gene‐specific selection, finally resulting in the stratified differentiation occurring between 0–20 and 20–100 cm. These results enhance our cognition of the microbial adaptation mechanisms to vertical environmental changes during the sedimentation process of coastal blue carbon ecosystems. [ABSTRACT FROM AUTHOR]

Adipogenesis, a pivotal cellular process involving the differentiation of mesenchymal stem cells (MSCs) to mature adipocytes, plays a significant role in various physiological functions. Dysregulation of adipogenesis is implicated in conditions such as obesity. However, the complete molecular understanding of adipogenesis remains elusive. This study aimed to uncover the novel role of lamina‐associated polypeptide 2 alpha (LAP2α) in human adipose‐derived stem cells (hASCs) adipogenesis and its impact on high‐fat diet (HFD)‐induced obesity and associated metabolic disturbances. LAP2α expression was assessed during the adipogenic differentiation of hASCs using RT‐qPCR and western blotting. The functional role of LAP2α in adipogenesis was explored both in vitro and in vivo through loss‐ and gain‐of‐function studies. Moreover, mice with HFD‐induced obesity received lentivirus injection to assess the effect of LAP2α knockdown on fat accumulation. Molecular mechanisms underlying LAP2α in adipogenic differentiation were investigated using RT‐qPCR, Western blotting, immunofluorescence staining, and Oil Red O staining. LAP2α expression was upregulated during hASCs adipogenic differentiation. LAP2α knockdown hindered adipogenesis, while LAP2α overexpression promoted adipogenic differentiation. Notably, LAP2α deficiency resisted HFD‐induced obesity, improved glucose intolerance, mitigated insulin resistance, and prevented fatty liver development. Mechanistically, LAP2α knockdown attenuated signal transducer and activator of transcription 3 (STAT3) activation by reducing the protein level of phosphorylated STAT3. A STAT3 activator (Colivelin) counteracted the negative impact of LAP2α deficiency on hASCs adipogenic differentiation. Taken together, our current study established LAP2α as a crucial regulator of hASCs adipogenic differentiation, unveiling a new therapeutic target for obesity prevention. [ABSTRACT FROM AUTHOR]

Methane is a critical greenhouse gas with significant impacts on environmental and global change. However, CH4 cycling processes and coupling mechanisms with the biogeochemical cycling of carbon, nitrogen, sulfur and metals in the environment remain elusive. To fill such knowledge gaps, we constructed a manually curated methane cycling database (MCycDB) for comprehensive and accurate analysis of methane cycling microbial communities. MCycDB contains 298 methane cycling gene families covering 10 methane metabolism pathways with 610,208 representative sequences, and associated reference sequences from the NCBI RefSeq database with 48 phyla and 2,197 genera, and five phyla and 100 genera for bacteria and archaea, respectively. Also, homologous groups from public orthology databases were identified and included in MCycDB to reduce false positive assignments. We applied MCycDB to profile methane cycling gene families and associated taxonomic groups from various environments. Gene families involved in methanogenesis were abundant in hot spring sediment and less abundant in freshwater, whereas the ones involved in aerobic oxidation of methane were abundant in permafrost and peatland. This study demonstrates that MCycDB is a useful tool for studying microbially‐driven methane cycling processes with high specificity, coverage and accuracy. [ABSTRACT FROM AUTHOR]

Preeclampsia, characterized by high blood pressure, albuminuria and other systemic disorders, is a serious complication during pregnancy. It has been reported that GNA12 is overexpressed during preeclampsia. In this study, we investigated the potential association between the methylation of the GNA12 promoter and preeclampsia. The methylation level at eight CpG sites of the GNA12 promoter was analyzed by MassARRAY in placenta and peripheral blood DNA samples from 50 preeclampsia patients and 50 normal pregnant women. In the placenta DNA samples, the methylation level at three CpG sites of the GNA12 promoter was significantly lower in the preeclampsia patients than in the controls. The difference was also significant at two of the three CpG sites in the peripheral blood DNA samples. The mRNA expression level of GNA12 in placenta was analyzed by real-time quantitative PCR in 20 cases and 20 controls. Consistent with the decreased methylation level, the mRNA expression level of GNA12 was higher in preeclampsia patients than in controls. Our results showed that preeclampsia is associated with decreased methylation of the GNA12 promoter, which can be detected in both the placenta and the peripheral blood of the pregnant women. [ABSTRACT FROM AUTHOR]