MicroRNAs are -22 nt long small non-coding RNAs that play important regulatory roles in eukaryotes. The biogenesis and functional processes of microRNAs require the participation of many proteins, of which, the well s...MicroRNAs are -22 nt long small non-coding RNAs that play important regulatory roles in eukaryotes. The biogenesis and functional processes of microRNAs require the participation of many proteins, of which, the well studied ones are Dicer, Drosha, Argonaute and Exportin 5. To systematically study these four protein families, we screened 11 animal genomes to search for genes encoding above mentioned proteins, and identified some new members for each family. Domain analysis results revealed that most proteins within the same family share identical or similar domains. Alternative spliced transcript variants were found for some proteins. We also examined the expression patterns of these proteins in different human tissues and identified other proteins that could potentially interact with these proteins. These findings provided systematic information on the four key proteins involved in microRNA biogenesis and functional pathways in animals, and will shed light on further functional studies of these proteins.展开更多
Haploid pluripotent stem cells,such as haploid embryonic stem cells(haESCs),facilitate the genetic study of recessive traits.In vitro,fish haESCs maintain haploidy in both undifferentiated and differentiated states,bu...Haploid pluripotent stem cells,such as haploid embryonic stem cells(haESCs),facilitate the genetic study of recessive traits.In vitro,fish haESCs maintain haploidy in both undifferentiated and differentiated states,but whether mammalian haESCs can preserve pluripotency in the haploid state has not been tested.Here,wereport thatmousehaESCs can differentiate in vitro into haploid epiblast stem cells(haEpiSCs),which maintain an intact haploid genome,unlimited self-renewal potential,and durable pluripotency to differentiate into various tissues in vitro and in vivo.Mechanistically,the maintenance of self-renewal potential depends on the Activin/bFGF pathway.We further show that haEpiSCs can differentiate in vitro into haploid progenitor-like cells.When injected into the cytoplasm of an oocyte,androgenetic haEpiSC(ahaEpiSCs)can support embryonic development until midgestation(E12.5).Together,these resultsdemonstrate durable pluripotency inmousehaESCs andhaEpiSCs,aswell asthe valuable potential of using these haploid pluripotent stem cells in high-throughput genetic screening.展开更多
基金supported by grants from the Ministry of Science and Technology of China (No. 2007CB946901)the Natural Science Foundation of China (No. 30725014 and 90612019)the Chinese Academy of Sciences (No. KSCX2-YW-R-134)
文摘MicroRNAs are -22 nt long small non-coding RNAs that play important regulatory roles in eukaryotes. The biogenesis and functional processes of microRNAs require the participation of many proteins, of which, the well studied ones are Dicer, Drosha, Argonaute and Exportin 5. To systematically study these four protein families, we screened 11 animal genomes to search for genes encoding above mentioned proteins, and identified some new members for each family. Domain analysis results revealed that most proteins within the same family share identical or similar domains. Alternative spliced transcript variants were found for some proteins. We also examined the expression patterns of these proteins in different human tissues and identified other proteins that could potentially interact with these proteins. These findings provided systematic information on the four key proteins involved in microRNA biogenesis and functional pathways in animals, and will shed light on further functional studies of these proteins.
基金supported by grants from the National Basic Research Program of China(2012CBA01300 to Q.Z.and 2014CB964800 to W.L.)the National Science Foundation of China(91319308 to Q.Z.).
文摘Haploid pluripotent stem cells,such as haploid embryonic stem cells(haESCs),facilitate the genetic study of recessive traits.In vitro,fish haESCs maintain haploidy in both undifferentiated and differentiated states,but whether mammalian haESCs can preserve pluripotency in the haploid state has not been tested.Here,wereport thatmousehaESCs can differentiate in vitro into haploid epiblast stem cells(haEpiSCs),which maintain an intact haploid genome,unlimited self-renewal potential,and durable pluripotency to differentiate into various tissues in vitro and in vivo.Mechanistically,the maintenance of self-renewal potential depends on the Activin/bFGF pathway.We further show that haEpiSCs can differentiate in vitro into haploid progenitor-like cells.When injected into the cytoplasm of an oocyte,androgenetic haEpiSC(ahaEpiSCs)can support embryonic development until midgestation(E12.5).Together,these resultsdemonstrate durable pluripotency inmousehaESCs andhaEpiSCs,aswell asthe valuable potential of using these haploid pluripotent stem cells in high-throughput genetic screening.
