Genes encoding enzymes involved in biosynthesis of very long chain fatty acids were significantly up-regulatedduring early cotton fiber development. Two cDNAs, GhKCR1 and GhKCR2 encoding putative cotton 3-ketoacyl-CoA...Genes encoding enzymes involved in biosynthesis of very long chain fatty acids were significantly up-regulatedduring early cotton fiber development. Two cDNAs, GhKCR1 and GhKCR2 encoding putative cotton 3-ketoacyl-CoAreductases that catalyze the second step in fatty acid elongation, were isolated from developing cotton fibers. GhKCR1and 2 contain open reading frames of 963 bp and 924 bp encoding proteins of 320 and 307 amino acid residues,respectively. Quantatitive RT-PCR analysis showed that both these genes were highly preferentially expressed duringthe cotton fiber elongation period with much lower levels recovered from roots, stems and leaves. GhKCR1 and 2showed 30%-32% identity to Saccharomyces cerevisiae Ybr159p at the deduced amino acid level. These cotton cDNAswere cloned and expressed in yeast haploid ybr159w? mutant that was deficient in 3-ketoacyl-CoA reductase activity.Wild-type growth rate was restored in ybr159w? cells that expressed either GhKCR1 or 2. Further analysis showed thatGhKCR1 and 2 were co-sedimented within the membranous pellet fraction after high-speed centrifugation, similar to theyeast endoplasmic reticulum marker ScKar2p. Both GhKCR(s) showed NADPH-dependent 3-ketoacyl-CoA reductaseactivity in an in vitro assay system using palmitoyl-CoA and malonyl-CoA as substrates. Our results suggest thatGhKCR1 and 2 are functional orthologues of ScYbr159p.展开更多
Auxin plays a critical role in lateral root(LR)formation.The signaling module composed of auxin-response factors(ARFs)and lateral organ boundaries domain transcription factors mediates auxin signaling to control almos...Auxin plays a critical role in lateral root(LR)formation.The signaling module composed of auxin-response factors(ARFs)and lateral organ boundaries domain transcription factors mediates auxin signaling to control almost every stage of LR development.Here,we show that auxin-induced degradation of the APETALA2/Ethylene Responsive Factor(AP2/ERF)transcription factor ERF13,dependent on MITOGENACTIVATED PROTEIN KINASE MPK14-mediated phosphorylation,plays an essential role in LR development.Overexpression of ERF13 results in restricted passage of the LR primordia through the endodermal layer,greatly reducing LR emergence,whereas the erf13 mutants showed an increase in emerged LR.ERF13 inhibits the expression of 3-ketoacyl-CoA synthase16(KCS16),which encodes a fatty acid elongase involved in very-long-chain fatty acid(VLCFA)biosynthesis.Overexpression of KCS16 or exogenous VLCFA treatment rescues the LR emergence defects in ERF13 overexpression lines,indicating a role downstream of the auxin-MPK14-ERF13 signaling module.Collectively,our study uncovers a novel molecular mechanism by which MPK14-mediated auxin signaling modulates LR development via ERF13-regulated VLCFA biosynthesis.展开更多
The pathogenesis of very-long-chain acyl-CoA dehydrogenase(VLCAD)deficiency is highly heterogeneous and still unclear.Additional novel variants have been recently detected in the population.The molecular and cellular ...The pathogenesis of very-long-chain acyl-CoA dehydrogenase(VLCAD)deficiency is highly heterogeneous and still unclear.Additional novel variants have been recently detected in the population.The molecular and cellular effects of these previously unreported variants are still poorly understood and require further characterization.To address this problem,we have evaluated the various functions and biochemical consequences of six novel missense variants that lead to mild VLCAD deficiency.Marked deficiencies in fatty acid oxidation(FAO)and other mitochondrial defects were observed in cells carrying one of these six variants(c.541 C>T,c.863 T>G,c.895 A>G,c.1238 T>C,c.1276 G>A,and c.1505 T>A),including reductions in mitochondrial respiratory-chain function and adenosine teriphosphate(ATP)production,and increased levels of mitochondrial reactive oxygen species(ROS).Intriguingly,higher apoptosis levels were found in cells carrying the mutant VLCAD under glucose-limited stress.Moreover,the stability of the mutant homodimer was disturbed,and major conformational changes in each mutant VLCAD structure were predicted by molecular dynamics(MD)simulation.The data presented here may provide valuable information for improving management of diagnosis and treatment of VLCAD deficiency and for a better understanding of the general molecular bases of disease variability.展开更多
Adrenomyeloneuropathy(AMN)is a kind of varied disease caused by ABCD1 gene mutation and characterized by very-long-chain fatty acids(VLCFA)accumulation.It is diag-nosed by clinical features,high VLCFAs levels and ABCD...Adrenomyeloneuropathy(AMN)is a kind of varied disease caused by ABCD1 gene mutation and characterized by very-long-chain fatty acids(VLCFA)accumulation.It is diag-nosed by clinical features,high VLCFAs levels and ABCD1 gene mutation.AMN is rarely reported in Chinese population.In this study,we report the genetic and clinical features of a Chinese pure AMN patient.Meanwhile,we conducted a literature review of AMN cases to summarize the characteristics of AMN.We report a rare Chinese pure AMN case with slowly progressive weakness of the lower extremities,caused by a novel c.1202G>A mutation in ABCD1 gene.The literature review indicates that spastic paraplegia is the mainly clinical manifestation in patients with AMN.VLCFAs and ABCD1 gene test should be performed in patients with spastic paraplegia of the lower limbs to diagnose AMN.展开更多
【目的】有着“水稻癌症”之称的稻瘟病严重危害水稻生产,鉴定稻瘟病菌致病关键因子并以此作为靶标开发有效农药,对防控该病害具有重大意义。【方法】目前,虽已报道隔蛋白septin调控稻瘟病菌致病性,但其分子作用机理并不清楚,也尚未开发...【目的】有着“水稻癌症”之称的稻瘟病严重危害水稻生产,鉴定稻瘟病菌致病关键因子并以此作为靶标开发有效农药,对防控该病害具有重大意义。【方法】目前,虽已报道隔蛋白septin调控稻瘟病菌致病性,但其分子作用机理并不清楚,也尚未开发以septin功能为靶标的农药,于是我们利用遗传、生化、细胞生物和植物病理学等技术手段,对稻瘟病菌septin组装调控机制开展了分析。【结果】我们发现超长链脂肪酸(VLCFAs)对septin介导的致病起关键作用,并发现靶向抑制VLCFAs合成的metazachlor和diallate等药物对稻瘟病、玉米小斑病、小麦白粉病等真菌病害具有广谱防治效果,相关研究成果以“Discovery of broad-spectrum fungicides that block septin-dependent infection processes of pathogenic fungi”为题于2020年9月发表在国际期刊Nature Microbiology(doi.org/10.1038/s41564-020-00790-y)。【结论】该成果揭示了septin介导真菌致病的新机制,并为防治动植物真菌病害提供了新方案和新药物。展开更多
基金supported by grants from China Na-tional Basic Research Program (NO. 2004CB117302)National Natural Science Foundation of China (No.30470171)the Sigrid Jusélius Foundation Finland and the Academy of Finland
文摘Genes encoding enzymes involved in biosynthesis of very long chain fatty acids were significantly up-regulatedduring early cotton fiber development. Two cDNAs, GhKCR1 and GhKCR2 encoding putative cotton 3-ketoacyl-CoAreductases that catalyze the second step in fatty acid elongation, were isolated from developing cotton fibers. GhKCR1and 2 contain open reading frames of 963 bp and 924 bp encoding proteins of 320 and 307 amino acid residues,respectively. Quantatitive RT-PCR analysis showed that both these genes were highly preferentially expressed duringthe cotton fiber elongation period with much lower levels recovered from roots, stems and leaves. GhKCR1 and 2showed 30%-32% identity to Saccharomyces cerevisiae Ybr159p at the deduced amino acid level. These cotton cDNAswere cloned and expressed in yeast haploid ybr159w? mutant that was deficient in 3-ketoacyl-CoA reductase activity.Wild-type growth rate was restored in ybr159w? cells that expressed either GhKCR1 or 2. Further analysis showed thatGhKCR1 and 2 were co-sedimented within the membranous pellet fraction after high-speed centrifugation, similar to theyeast endoplasmic reticulum marker ScKar2p. Both GhKCR(s) showed NADPH-dependent 3-ketoacyl-CoA reductaseactivity in an in vitro assay system using palmitoyl-CoA and malonyl-CoA as substrates. Our results suggest thatGhKCR1 and 2 are functional orthologues of ScYbr159p.
基金This research was supported by the National Natural Science Foundation of China(Projects 31670275,31470371,31500227,and 31900246)the Shandong Province Natural Science Foundation Major Basic Research Program(2017C03)+1 种基金the China Postdoctoral Science Foundation(2019M662332,2019T120582)the Special Support for Post-doc Creative Funding in Shandong(201901010).
文摘Auxin plays a critical role in lateral root(LR)formation.The signaling module composed of auxin-response factors(ARFs)and lateral organ boundaries domain transcription factors mediates auxin signaling to control almost every stage of LR development.Here,we show that auxin-induced degradation of the APETALA2/Ethylene Responsive Factor(AP2/ERF)transcription factor ERF13,dependent on MITOGENACTIVATED PROTEIN KINASE MPK14-mediated phosphorylation,plays an essential role in LR development.Overexpression of ERF13 results in restricted passage of the LR primordia through the endodermal layer,greatly reducing LR emergence,whereas the erf13 mutants showed an increase in emerged LR.ERF13 inhibits the expression of 3-ketoacyl-CoA synthase16(KCS16),which encodes a fatty acid elongase involved in very-long-chain fatty acid(VLCFA)biosynthesis.Overexpression of KCS16 or exogenous VLCFA treatment rescues the LR emergence defects in ERF13 overexpression lines,indicating a role downstream of the auxin-MPK14-ERF13 signaling module.Collectively,our study uncovers a novel molecular mechanism by which MPK14-mediated auxin signaling modulates LR development via ERF13-regulated VLCFA biosynthesis.
基金the National Natural Science Foundation of China(No.81741090)the Zhejiang Provincial Program for the Cultivation of High-level Innovative Health Talentsthe National KePy R&D Program of China(Nos.2017YFC1001703 and 2018YFC1002700)。
文摘The pathogenesis of very-long-chain acyl-CoA dehydrogenase(VLCAD)deficiency is highly heterogeneous and still unclear.Additional novel variants have been recently detected in the population.The molecular and cellular effects of these previously unreported variants are still poorly understood and require further characterization.To address this problem,we have evaluated the various functions and biochemical consequences of six novel missense variants that lead to mild VLCAD deficiency.Marked deficiencies in fatty acid oxidation(FAO)and other mitochondrial defects were observed in cells carrying one of these six variants(c.541 C>T,c.863 T>G,c.895 A>G,c.1238 T>C,c.1276 G>A,and c.1505 T>A),including reductions in mitochondrial respiratory-chain function and adenosine teriphosphate(ATP)production,and increased levels of mitochondrial reactive oxygen species(ROS).Intriguingly,higher apoptosis levels were found in cells carrying the mutant VLCAD under glucose-limited stress.Moreover,the stability of the mutant homodimer was disturbed,and major conformational changes in each mutant VLCAD structure were predicted by molecular dynamics(MD)simulation.The data presented here may provide valuable information for improving management of diagnosis and treatment of VLCAD deficiency and for a better understanding of the general molecular bases of disease variability.
基金The study was supported by the National key R&D Program of China[grant numbers 2017YFC1310300,2016YFC1306600]the National Natural Science Foun-dation of China[grant numbers 81301081,81601127]。
文摘Adrenomyeloneuropathy(AMN)is a kind of varied disease caused by ABCD1 gene mutation and characterized by very-long-chain fatty acids(VLCFA)accumulation.It is diag-nosed by clinical features,high VLCFAs levels and ABCD1 gene mutation.AMN is rarely reported in Chinese population.In this study,we report the genetic and clinical features of a Chinese pure AMN patient.Meanwhile,we conducted a literature review of AMN cases to summarize the characteristics of AMN.We report a rare Chinese pure AMN case with slowly progressive weakness of the lower extremities,caused by a novel c.1202G>A mutation in ABCD1 gene.The literature review indicates that spastic paraplegia is the mainly clinical manifestation in patients with AMN.VLCFAs and ABCD1 gene test should be performed in patients with spastic paraplegia of the lower limbs to diagnose AMN.
文摘【目的】有着“水稻癌症”之称的稻瘟病严重危害水稻生产,鉴定稻瘟病菌致病关键因子并以此作为靶标开发有效农药,对防控该病害具有重大意义。【方法】目前,虽已报道隔蛋白septin调控稻瘟病菌致病性,但其分子作用机理并不清楚,也尚未开发以septin功能为靶标的农药,于是我们利用遗传、生化、细胞生物和植物病理学等技术手段,对稻瘟病菌septin组装调控机制开展了分析。【结果】我们发现超长链脂肪酸(VLCFAs)对septin介导的致病起关键作用,并发现靶向抑制VLCFAs合成的metazachlor和diallate等药物对稻瘟病、玉米小斑病、小麦白粉病等真菌病害具有广谱防治效果,相关研究成果以“Discovery of broad-spectrum fungicides that block septin-dependent infection processes of pathogenic fungi”为题于2020年9月发表在国际期刊Nature Microbiology(doi.org/10.1038/s41564-020-00790-y)。【结论】该成果揭示了septin介导真菌致病的新机制,并为防治动植物真菌病害提供了新方案和新药物。
