An increasing body of evidence shows that the lipid droplet,a neutral lipid storage organelle,plays a role in lipid metabolism and energy homeostasis through its interaction with mitochondria.However,the cellular func...An increasing body of evidence shows that the lipid droplet,a neutral lipid storage organelle,plays a role in lipid metabolism and energy homeostasis through its interaction with mitochondria.However,the cellular functions and molecular mechanisms of the interaction remain ambiguous.Here we present data from transmission electron microscopy,fluorescence imaging,and reconstitution assays,demonstrating that lipid droplets physically contact mitochondria in vivo and in vitro.Using a bimolecular fluorescence complementation assay in Saccharomyces cerevisiae,we generated an interactomic map of protein-protein contacts of lipid droplets with mitochondria and peroxisomes.The lipid droplet proteins Erg6 and Pet10 were found to be involved in 75%of the interactions detected.Interestingly,interactions between 3 pairs of lipid metabolic enzymes were detected.Collectively,these data demonstrate that lipid droplets make physical contacts with mitochondria and peroxisomes,and reveal specific molecular interactions that suggest active participation of lipid droplets in lipid metabolism in yeast.展开更多
环境内分泌干扰物(endocrine disrupting chemicals,EDCs)可模仿或拮抗天然激素与核受体结合,干扰核受体的同源或异源二聚,进而通过共调节因子的招募调控转录活性,最终引起内分泌干扰效应。目前研究主要针对EDCs与核受体的结合过程,忽...环境内分泌干扰物(endocrine disrupting chemicals,EDCs)可模仿或拮抗天然激素与核受体结合,干扰核受体的同源或异源二聚,进而通过共调节因子的招募调控转录活性,最终引起内分泌干扰效应。目前研究主要针对EDCs与核受体的结合过程,忽视了其对核受体二聚化过程的影响,而该过程的阻断可直接导致转录失活。EDCs对于不同核受体二聚化的影响不同,只有激动剂EDCs能够促进雄激素受体(androgen receptor,AR)的同源二聚化,而雌激素受体(estrogen receptor,ER)在与具有激动或拮抗活性的EDCs结合后都可诱导ER二聚体的形成,但二聚化类型不同。通过检索ToxCast和Tox21数据库发现多达227种EDCs可以诱导ER二聚化,相比于ERα-ERα同源二聚体(6.09%~7.38%的活性率),EDCs更易诱导ERα-ERβ异源二聚体(11.25%~12.22%的活性率)和ERβ-ERβ同源二聚体(10.02%~11.69%的活性率)。EDCs也能够差异性诱导其他核受体如维生素D受体(vitamin D receptor,VDR)与维甲酸X受体(retinoid X receptor,RXR)形成的异源二聚体,不同类型的二聚体对于研究EDCs转录活性的生理学相关性具有重要意义。基于经济合作与发展组织(Organization for Economic Co-operation and Development,OECD)报告的参考化学品研究发现,相比于配受体结合活性,二聚活性与转录活性之间有着更好的相关关系。本文从EDCs介导的核受体二聚化转录机制、二聚化与转录活性间的关系以及二聚化研究方法三方面,总结EDCs对核受体二聚化的影响,以期为深入理解EDCs的分子作用机制,推进化合物的内分泌干扰风险评估提供参考。展开更多
基金supported by grants from the National Basic Research Program of China(Grant Nos.2009CB919000 and 2010CB833703)the National Natural Science Foundation of China(Grant Nos.30871229 and 30971431)the 21C Frontier Functional Proteomics Project(FPR08A1-060)funded by the Ministry of Education,Science and Technology,Republic of Korea.
文摘An increasing body of evidence shows that the lipid droplet,a neutral lipid storage organelle,plays a role in lipid metabolism and energy homeostasis through its interaction with mitochondria.However,the cellular functions and molecular mechanisms of the interaction remain ambiguous.Here we present data from transmission electron microscopy,fluorescence imaging,and reconstitution assays,demonstrating that lipid droplets physically contact mitochondria in vivo and in vitro.Using a bimolecular fluorescence complementation assay in Saccharomyces cerevisiae,we generated an interactomic map of protein-protein contacts of lipid droplets with mitochondria and peroxisomes.The lipid droplet proteins Erg6 and Pet10 were found to be involved in 75%of the interactions detected.Interestingly,interactions between 3 pairs of lipid metabolic enzymes were detected.Collectively,these data demonstrate that lipid droplets make physical contacts with mitochondria and peroxisomes,and reveal specific molecular interactions that suggest active participation of lipid droplets in lipid metabolism in yeast.
文摘环境内分泌干扰物(endocrine disrupting chemicals,EDCs)可模仿或拮抗天然激素与核受体结合,干扰核受体的同源或异源二聚,进而通过共调节因子的招募调控转录活性,最终引起内分泌干扰效应。目前研究主要针对EDCs与核受体的结合过程,忽视了其对核受体二聚化过程的影响,而该过程的阻断可直接导致转录失活。EDCs对于不同核受体二聚化的影响不同,只有激动剂EDCs能够促进雄激素受体(androgen receptor,AR)的同源二聚化,而雌激素受体(estrogen receptor,ER)在与具有激动或拮抗活性的EDCs结合后都可诱导ER二聚体的形成,但二聚化类型不同。通过检索ToxCast和Tox21数据库发现多达227种EDCs可以诱导ER二聚化,相比于ERα-ERα同源二聚体(6.09%~7.38%的活性率),EDCs更易诱导ERα-ERβ异源二聚体(11.25%~12.22%的活性率)和ERβ-ERβ同源二聚体(10.02%~11.69%的活性率)。EDCs也能够差异性诱导其他核受体如维生素D受体(vitamin D receptor,VDR)与维甲酸X受体(retinoid X receptor,RXR)形成的异源二聚体,不同类型的二聚体对于研究EDCs转录活性的生理学相关性具有重要意义。基于经济合作与发展组织(Organization for Economic Co-operation and Development,OECD)报告的参考化学品研究发现,相比于配受体结合活性,二聚活性与转录活性之间有着更好的相关关系。本文从EDCs介导的核受体二聚化转录机制、二聚化与转录活性间的关系以及二聚化研究方法三方面,总结EDCs对核受体二聚化的影响,以期为深入理解EDCs的分子作用机制,推进化合物的内分泌干扰风险评估提供参考。
