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Oyundari Amartuvshin Chi‐Hung Lin Shao‐Chun Hsu Shih‐Han Kao Alvin Chen Wei‐Chun Tang Han‐Lin Chou Dong‐Lin Chang Yen‐Yang Hsu Bai‐Shiou Hsiao Elham Rastegari Kun‐Yang Lin Yu‐Ting Wang Chi‐Kuang Yao Guang‐Chao Chen Bi‐Chang Chen Hwei‐Jan Hsu 《Aging cell》2020,19(8)
Changes in mitochondrial dynamics (fusion and fission) are known to occur during stem cell differentiation; however, the role of this phenomenon in tissue aging remains unclear. Here, we report that mitochondrial dynamics are shifted toward fission during aging of Drosophila ovarian germline stem cells (GSCs), and this shift contributes to aging‐related GSC loss. We found that as GSCs age, mitochondrial fragmentation and expression of the mitochondrial fission regulator, Dynamin‐related protein (Drp1), are both increased, while mitochondrial membrane potential is reduced. Moreover, preventing mitochondrial fusion in GSCs results in highly fragmented depolarized mitochondria, decreased BMP stemness signaling, impaired fatty acid metabolism, and GSC loss. Conversely, forcing mitochondrial elongation promotes GSC attachment to the niche. Importantly, maintenance of aging GSCs can be enhanced by suppressing Drp1 expression to prevent mitochondrial fission or treating with rapamycin, which is known to promote autophagy via TOR inhibition. Overall, our results show that mitochondrial dynamics are altered during physiological aging, affecting stem cell homeostasis via coordinated changes in stemness signaling, niche contact, and cellular metabolism. Such effects may also be highly relevant to other stem cell types and aging‐induced tissue degeneration. 相似文献
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Hien Van Doan Seyed Hossein Hoseinifar Wanaporn Tapingkae Mintra Seel-audom Sanchai Jaturasitha Mahmoud A. O. Dawood Sutee Wongmaneeprateep Tran Thi Nang Thu Maria ngeles Esteban 《Probiotics and antimicrobial proteins》2020,12(2):400-411
The present work, herein, studied the effects of corncob-derived xylooligosaccharides (CDXOS) and Lactobacillus plantarum CR1T5 (LP) integrated into fish d 相似文献
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A new temperate wood bamboo endemic to Vietnam is described and illustrated as Chimonocalamus bidoupensis N.H.Nghia & V.T.Tran. The new species is similar to C. baviensis in general appearance, but differs by its densely ciliate culms, culm sheaths that are concave at the apex with dense, white hairs on the abaxial surface of the sheath, and perfect florets 7–8 mm long. 相似文献
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ChiWei Yeh WeiChieh Huang PangHung Hsu KunHai Yeh LiChin Wang Paul WeiChe Hsu HsiuChuan Lin YiNing Chen ShuChuan Chen ChenHsiang Yeang HsuehChi S Yen 《The EMBO journal》2021,40(7)
Protein termini are determinants of protein stability. Proteins bearing degradation signals, or degrons, at their amino‐ or carboxyl‐termini are eliminated by the N‐ or C‐degron pathways, respectively. We aimed to elucidate the function of C‐degron pathways and to unveil how normal proteomes are exempt from C‐degron pathway‐mediated destruction. Our data reveal that C‐degron pathways remove mislocalized cellular proteins and cleavage products of deubiquitinating enzymes. Furthermore, the C‐degron and N‐degron pathways cooperate in protein removal. Proteome analysis revealed a shortfall in normal proteins targeted by C‐degron pathways, but not of defective proteins, suggesting proteolysis‐based immunity as a constraint for protein evolution/selection. Our work highlights the importance of protein termini for protein quality surveillance, and the relationship between the functional proteome and protein degradation pathways. 相似文献
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Sarah Findakly Vikas Daggubati Galo Garcia III Sydney A. LaStella Abrar Choudhury Cecilia Tran Amy Li Pakteema Tong Jason Q. Garcia Natasha Puri Jeremy F. Reiter Libin Xu David R. Raleigh 《The Journal of cell biology》2021,220(1)
Vertebrate Hedgehog signals are transduced through the primary cilium, a specialized lipid microdomain that is required for Smoothened activation. Cilia-associated sterol and oxysterol lipids bind to Smoothened to activate the Hedgehog pathway, but how ciliary lipids are regulated is incompletely understood. Here we identified DHCR7, an enzyme that produces cholesterol, activates the Hedgehog pathway, and localizes near the ciliary base. We found that Hedgehog stimulation negatively regulates DHCR7 activity and removes DHCR7 from the ciliary microenvironment, suggesting that DHCR7 primes cilia for Hedgehog pathway activation. In contrast, we found that Hedgehog stimulation positively regulates the oxysterol synthase CYP7A1, which accumulates near the ciliary base and produces oxysterols that promote Hedgehog signaling in response to pathway activation. Our results reveal that enzymes involved in lipid biosynthesis in the ciliary microenvironment promote Hedgehog signaling, shedding light on how ciliary lipids are established and regulated to transduce Hedgehog signals. 相似文献