Mint is a newly identified molecule that mediates signal transduction and modulates chromatin repression. Mint family members contain a highly conserved C-terminus SPOC domain (SpenParalog and OrthologsC-terminal doma...Mint is a newly identified molecule that mediates signal transduction and modulates chromatin repression. Mint family members contain a highly conserved C-terminus SPOC domain (SpenParalog and OrthologsC-terminal domain) commonly associated with proliferation and related diseases (for example: cancer) due to its role in cell differentiation and apoptosis. In this study, we addressed the SPOC function using a tetracycline-inducible system to express the target domain in Ain V15 embryonic ES cells and bone marrow stem cells from SPOC transenic mice. In vitro differentiation of Ain V15 ES cells as a model of early hematopoietic development, we found expression of SPOC domain induces hematopoietic differentiation via up-regulation of transcription factors Bmp4 and Smad5, which induce the expression of hematopoietic factors Eklf1 and hematopoietic proliferation associated factor Gata2, the SPOC domain also plays the regulation function in the differentiation of hematopoitic progenitor by colony forming Unit (CFU) assays. Further, we determined SPOC expression enhances erythrocyte and granulocyte maturationusing bone marrow cells derived from tiSPOC chimeric mice. Finally, we identified that overexpression of full length Mint in ES cells drive Smad5 and Bmp4 up-regulation under culture conditions, and up-regulation of endogenous Mint when induceshematopoitic differentiation of EML, M1 and WT18 cells. In summary, our study reveals the conserved SPOC domain of Mint protein induces differentiation both in the stages of embryonic stem cells and hematopoietic progenitor cells.展开更多
Background: Intramuscular fat(IMF) content is a vital parameter for assessing pork quality. Increasing evidence has shown that microRNAs(miRNAs) play an important role in regulating porcine IMF deposition. Here, a nov...Background: Intramuscular fat(IMF) content is a vital parameter for assessing pork quality. Increasing evidence has shown that microRNAs(miRNAs) play an important role in regulating porcine IMF deposition. Here, a novel miRNA implicated in porcine IMF adipogenesis was found, and its effect and regulatory mechanism were further explored with respect to intramuscular preadipocyte proliferation and differentiation.Results: By porcine adipose tissue miRNA sequencing analysis, we found that miR-146a-5p is a potential regulator of porcine IMF adipogenesis. Further studies showed that miR-146a-5p mimics inhibited porcine intramuscular preadipocyte proliferation and differentiation, while the miR-146a-5p inhibitor promoted cell proliferation and adipogenic differentiation. Mechanistically, miR-146a-5p suppressed cell proliferation by directly targeting SMAD family member 4(SMAD4) to attenuate TGF-β signaling. Moreover, miR-146a-5p inhibited the differentiation of intramuscular preadipocytes by targeting TNF receptor-associated factor 6(TRAF6) to weaken the AKT/mTORC1 signaling downstream of the TRAF6 pathway.Conclusions: MiR-146a-5p targets SMAD4 and TRAF6 to inhibit porcine intramuscular adipogenesis by attenuating TGF-β and AKT/mTORC1 signaling, respectively. These findings provide a novel miRNA biomarker for regulating intramuscular adipogenesis to promote pork quality.展开更多
文摘Mint is a newly identified molecule that mediates signal transduction and modulates chromatin repression. Mint family members contain a highly conserved C-terminus SPOC domain (SpenParalog and OrthologsC-terminal domain) commonly associated with proliferation and related diseases (for example: cancer) due to its role in cell differentiation and apoptosis. In this study, we addressed the SPOC function using a tetracycline-inducible system to express the target domain in Ain V15 embryonic ES cells and bone marrow stem cells from SPOC transenic mice. In vitro differentiation of Ain V15 ES cells as a model of early hematopoietic development, we found expression of SPOC domain induces hematopoietic differentiation via up-regulation of transcription factors Bmp4 and Smad5, which induce the expression of hematopoietic factors Eklf1 and hematopoietic proliferation associated factor Gata2, the SPOC domain also plays the regulation function in the differentiation of hematopoitic progenitor by colony forming Unit (CFU) assays. Further, we determined SPOC expression enhances erythrocyte and granulocyte maturationusing bone marrow cells derived from tiSPOC chimeric mice. Finally, we identified that overexpression of full length Mint in ES cells drive Smad5 and Bmp4 up-regulation under culture conditions, and up-regulation of endogenous Mint when induceshematopoitic differentiation of EML, M1 and WT18 cells. In summary, our study reveals the conserved SPOC domain of Mint protein induces differentiation both in the stages of embryonic stem cells and hematopoietic progenitor cells.
基金supported by grants from the National Natural Science Foundation (31872979, 31572366)the National Key Research and Development Program of China (2017YFD0502002)the National Basic Research Programs of China (2015CB943102)。
文摘Background: Intramuscular fat(IMF) content is a vital parameter for assessing pork quality. Increasing evidence has shown that microRNAs(miRNAs) play an important role in regulating porcine IMF deposition. Here, a novel miRNA implicated in porcine IMF adipogenesis was found, and its effect and regulatory mechanism were further explored with respect to intramuscular preadipocyte proliferation and differentiation.Results: By porcine adipose tissue miRNA sequencing analysis, we found that miR-146a-5p is a potential regulator of porcine IMF adipogenesis. Further studies showed that miR-146a-5p mimics inhibited porcine intramuscular preadipocyte proliferation and differentiation, while the miR-146a-5p inhibitor promoted cell proliferation and adipogenic differentiation. Mechanistically, miR-146a-5p suppressed cell proliferation by directly targeting SMAD family member 4(SMAD4) to attenuate TGF-β signaling. Moreover, miR-146a-5p inhibited the differentiation of intramuscular preadipocytes by targeting TNF receptor-associated factor 6(TRAF6) to weaken the AKT/mTORC1 signaling downstream of the TRAF6 pathway.Conclusions: MiR-146a-5p targets SMAD4 and TRAF6 to inhibit porcine intramuscular adipogenesis by attenuating TGF-β and AKT/mTORC1 signaling, respectively. These findings provide a novel miRNA biomarker for regulating intramuscular adipogenesis to promote pork quality.
