Background Pork quality is affected by the type of muscle fibers, which is closely related to meat color, tenderness and juiciness. Exosomes are tiny vesicles with a diameter of approximately 30–150 nm that are secre...Background Pork quality is affected by the type of muscle fibers, which is closely related to meat color, tenderness and juiciness. Exosomes are tiny vesicles with a diameter of approximately 30–150 nm that are secreted by cells and taken up by recipient cells to mediate communication. Exosome-mediated muscle-fat tissue crosstalk is a newly discovered mechanism that may have an important effect on intramuscular fat deposition and with that on meat quality. Various of adipose tissue-derived exosomes have been discovered and identified, but the identification and function of muscle exosomes, especially porcine fast/slow myotube exosomes, remain unclear. Here, we first isolated and identified exosomes secreted from porcine extensor digitorum longus(EDL) and soleus(SOL), which represent fast and slow muscle, respectively, and further explored their effects on lipid accumulation in longissimus dorsi adipocytes.Results Porcine SOL-derived exosomes(SOL-EXO) and EDL-derived exosomes(EDL-EXO) were first identified and their average particle sizes were approximately 84 nm with double-membrane disc-shapes as observed via transmission electron microscopy and scanning electron microscopy. Moreover, the intramuscular fat content of the SOL was greater than that of the EDL at 180 days of age, because SOL intramuscular adipocytes had a stronger lipid-accumulating capacity than those of the EDL. Raman spectral analysis revealed that SOL-EXO protein content was much greater than that of EDL-EXO. Proteomic sequencing identified 72 proteins that were significantly differentially expressed between SOL-EXO and EDL-EXO, 31 of which were downregulated and 41 of which were upregulated in SOL-EXO.Conclusions Our findings suggest that muscle-fat tissue interactions occur partly via SOL-EXO promoting adipogenic activity of intramuscular adipocytes.展开更多
Background Long non-coding RNAs(lncRNAs)regulate numerous biological processes,including adipogenesis.Research on adipogenesis will assist in the treatment of human metabolic diseases and improve meat quality in lives...Background Long non-coding RNAs(lncRNAs)regulate numerous biological processes,including adipogenesis.Research on adipogenesis will assist in the treatment of human metabolic diseases and improve meat quality in livestock,such as the content of intramuscular fat(IMF).However,the significance of lncRNAs in intramuscular adipogenesis remains unclear.This research aimed to reveal the lncRNAs transcriptomic profiles in the process of bovine intramuscular adipogenesis and to identify the lncRNAs involved in the adipogenesis of bovine intramuscular adipocytes.Results In this research,a landscape of lncRNAs was identified with RNA-seq in bovine intramuscular adipocytes at four adipogenesis stages(0 d,3 d,6 d,and 9 d after differentiation).A total of 7035 lncRNAs were detected,including 3396 novel lncRNAs.Based on the results of differential analysis,co-expression analysis,and functional prediction,we focused on the bovine intramuscular adipogenesis-associated long non-coding RNA(BIANCR),a novel lncRNA that may have an important regulatory function.The knockdown of BIANCR inhibited proliferation and promoted apoptosis of intramuscular preadipocytes.Moreover,BIANCR knockdown inhibited intramuscular adipogenesis by regulating the ERK1/2 signaling pathway.Conclusion This study obtained the landscape of lncRNAs during adipogenesis in bovine intramuscular adipocytes.BIANCR plays a crucial role in adipogenesis through the ERK1/2 signaling pathway.The results are noteworthy for improving beef meat quality,molecular breeding,and metabolic disease research.展开更多
The interaction between myocytes and intramuscular adipocytes is a hot scientific topic. Using a co-culture system, this study aims to investigate the regulation of intramuscular fat deposition in chicken muscle tissu...The interaction between myocytes and intramuscular adipocytes is a hot scientific topic. Using a co-culture system, this study aims to investigate the regulation of intramuscular fat deposition in chicken muscle tissue through the interaction between myocyte and adipocyte and identify important intermediary regulatory factors. Our proteomics data showed that the protein expression of tissue inhibitor of metalloproteinases 2(TIMP2) increased significantly in the culture medium of the co-culture system, and the content of lipid droplets was more in the co-culture intramuscular adipocytes. In addition, TIMP2 was significantly upregulated(P<0.01) in muscle tissue of individuals with high intramuscular fat content.Weighted gene co-expression network analysis revealed that TIMP2 was mainly involved in the extracellular matrix receptor interaction signaling pathway and its expression was significantly correlated with triglyceride, intramuscular fat,C14:0, C14:1, C16:0, C16:1, and C18:1n9C levels. Additionally, TIMP2 was co-expressed with various representative genes related to lipid metabolism(such as ADIPOQ, SCD, ELOVL5, ELOVL7, and LPL), as well as certain genes involved in extracellular matrix receptor interaction(such as COL1A2, COL4A2, COL5A1, COL6A1, and COL6A3), which are also significantly upregulated(P<0.05 or P<0.01) in muscle tissue of individuals with high intramuscular fat content.Our findings reveal that TIMP2 promotes intramuscular fat deposition in muscle tissue through the extracellular matrix receptor interaction signaling pathway.展开更多
基金supported by the National Natural Science Foundation of China (32272847, U22A20516)the Key Research and Development Program of Shaanxi Province (2022ZDLNY01-04)the China Agriculture Research System of MOF and MARA (CARS-35)。
文摘Background Pork quality is affected by the type of muscle fibers, which is closely related to meat color, tenderness and juiciness. Exosomes are tiny vesicles with a diameter of approximately 30–150 nm that are secreted by cells and taken up by recipient cells to mediate communication. Exosome-mediated muscle-fat tissue crosstalk is a newly discovered mechanism that may have an important effect on intramuscular fat deposition and with that on meat quality. Various of adipose tissue-derived exosomes have been discovered and identified, but the identification and function of muscle exosomes, especially porcine fast/slow myotube exosomes, remain unclear. Here, we first isolated and identified exosomes secreted from porcine extensor digitorum longus(EDL) and soleus(SOL), which represent fast and slow muscle, respectively, and further explored their effects on lipid accumulation in longissimus dorsi adipocytes.Results Porcine SOL-derived exosomes(SOL-EXO) and EDL-derived exosomes(EDL-EXO) were first identified and their average particle sizes were approximately 84 nm with double-membrane disc-shapes as observed via transmission electron microscopy and scanning electron microscopy. Moreover, the intramuscular fat content of the SOL was greater than that of the EDL at 180 days of age, because SOL intramuscular adipocytes had a stronger lipid-accumulating capacity than those of the EDL. Raman spectral analysis revealed that SOL-EXO protein content was much greater than that of EDL-EXO. Proteomic sequencing identified 72 proteins that were significantly differentially expressed between SOL-EXO and EDL-EXO, 31 of which were downregulated and 41 of which were upregulated in SOL-EXO.Conclusions Our findings suggest that muscle-fat tissue interactions occur partly via SOL-EXO promoting adipogenic activity of intramuscular adipocytes.
基金funded by the National Natural Science Foundation of China (31972994)Key Research and Development Program of Ningxia Province (2019BEF02004)+1 种基金National Beef and Yak Industrial Technology System (CARS-37)National Key Research and Development Program of China (2018YFD0501700)。
文摘Background Long non-coding RNAs(lncRNAs)regulate numerous biological processes,including adipogenesis.Research on adipogenesis will assist in the treatment of human metabolic diseases and improve meat quality in livestock,such as the content of intramuscular fat(IMF).However,the significance of lncRNAs in intramuscular adipogenesis remains unclear.This research aimed to reveal the lncRNAs transcriptomic profiles in the process of bovine intramuscular adipogenesis and to identify the lncRNAs involved in the adipogenesis of bovine intramuscular adipocytes.Results In this research,a landscape of lncRNAs was identified with RNA-seq in bovine intramuscular adipocytes at four adipogenesis stages(0 d,3 d,6 d,and 9 d after differentiation).A total of 7035 lncRNAs were detected,including 3396 novel lncRNAs.Based on the results of differential analysis,co-expression analysis,and functional prediction,we focused on the bovine intramuscular adipogenesis-associated long non-coding RNA(BIANCR),a novel lncRNA that may have an important regulatory function.The knockdown of BIANCR inhibited proliferation and promoted apoptosis of intramuscular preadipocytes.Moreover,BIANCR knockdown inhibited intramuscular adipogenesis by regulating the ERK1/2 signaling pathway.Conclusion This study obtained the landscape of lncRNAs during adipogenesis in bovine intramuscular adipocytes.BIANCR plays a crucial role in adipogenesis through the ERK1/2 signaling pathway.The results are noteworthy for improving beef meat quality,molecular breeding,and metabolic disease research.
基金funded by the grants from the National Natural Science Foundation of China(31872340)the State Key Laboratory of Animal Nutrition(2004DA125184G2109)+1 种基金the Agricultural Science and Technology Innovation Program of Chinese Academy of Agricultural Sciences(ASTIP-IAS04)the earmarked fund for China Agriculture Research System(CARS-41)。
文摘The interaction between myocytes and intramuscular adipocytes is a hot scientific topic. Using a co-culture system, this study aims to investigate the regulation of intramuscular fat deposition in chicken muscle tissue through the interaction between myocyte and adipocyte and identify important intermediary regulatory factors. Our proteomics data showed that the protein expression of tissue inhibitor of metalloproteinases 2(TIMP2) increased significantly in the culture medium of the co-culture system, and the content of lipid droplets was more in the co-culture intramuscular adipocytes. In addition, TIMP2 was significantly upregulated(P<0.01) in muscle tissue of individuals with high intramuscular fat content.Weighted gene co-expression network analysis revealed that TIMP2 was mainly involved in the extracellular matrix receptor interaction signaling pathway and its expression was significantly correlated with triglyceride, intramuscular fat,C14:0, C14:1, C16:0, C16:1, and C18:1n9C levels. Additionally, TIMP2 was co-expressed with various representative genes related to lipid metabolism(such as ADIPOQ, SCD, ELOVL5, ELOVL7, and LPL), as well as certain genes involved in extracellular matrix receptor interaction(such as COL1A2, COL4A2, COL5A1, COL6A1, and COL6A3), which are also significantly upregulated(P<0.05 or P<0.01) in muscle tissue of individuals with high intramuscular fat content.Our findings reveal that TIMP2 promotes intramuscular fat deposition in muscle tissue through the extracellular matrix receptor interaction signaling pathway.
