Project description:During angiosperm male gametogenesis, microspores divide to produce a vegetative cell (VC) and a male germline (MG), each with a distinct cell fate. How the MG cell/VC fate is determined remains largely unknown. Here, we report that the VC-targeted H3K27me3 erasure resulted in VC fate transition towards a gamete destination. Multi-omics and cytologic analysis reveal that H3K27me3 is essential for VC fate commitment and contributes to suppress the MG cell fate initiation in VC, whereas MG cells require H3K27me3 reprograming for the gamete cell fate. This work suggests that the MG cell/VC fate is epigenetically regulated. The dimorphic H3K27 methylation acts as a core switch to determine their distinct cell fates and ensure the functional specification of both VC and MG for pollen fertility. This work also provides direct evidences for the proposal that VC maintains the default developmental program of microspore, whereas MG requires reprogramming.
Project description:During angiosperm male gametogenesis, microspores divide to produce a vegetative cell (VC) and a male germline (MG), each with a distinct cell fate. How the MG cell/VC fate is determined remains largely unknown. Here, we report that the VC-targeted H3K27me3 erasure resulted in VC fate transition towards a gamete destination. Multi-omics and cytologic analysis reveal that H3K27me3 is essential for VC fate commitment and contributes to suppress the MG cell fate initiation in VC, whereas MG cells require H3K27me3 reprograming for the gamete cell fate. This work suggests that the MG cell/VC fate is epigenetically regulated. The dimorphic H3K27 methylation acts as a core switch to determine their distinct cell fates and ensure the functional specification of both VC and MG for pollen fertility. This work also provides direct evidences for the proposal that VC maintains the default developmental program of microspore, whereas MG requires reprogramming.
Project description:Organohalide-respiring Dehalococcoidia bacteria are one of the few microorganisms capable of transforming chlorinated solvents to benign ethene in anoxic environments. The tceA gene found in these bacteria, coding the trichloroethene-dechlorinating RDase TceA, is frequently detected in contaminated groundwater but not recognized as a biomarker for vinyl chloride detoxification. Here, we demonstrate that the tceA-carrying Dehalococcoides mccartyi (Dhc) strains FL2 and 195 grow with VC as electron acceptor when sufficient vitamin B12 is provided. Global proteomic profiling confirmed the predominant TceA expression in VC-grown Dhc FL2 cells, providing a line of evidence for the implication of TceA in respiratory VC reductive dechlorination.