线粒体 mRNA 修饰
中文名称
通路描述
线粒体 mRNA 包含 3'端多聚腺苷酸化、假尿苷化以及 N1-腺苷甲酰化，这些转录后修饰由核编码的蛋白质催化。线粒体 mRNA 的 3'端多聚腺苷酸化由 MTPAP（也称为 PAPD1）产生，这是一种位于细胞质和线粒体基质中的二聚体多聚腺苷酸聚合酶。与细胞质 mRNA 的多聚腺苷酸尾类似，线粒体多聚腺苷酸尾似乎有助于稳定 mRNA，但线粒体多聚腺苷酸尾（约 40-50 个腺苷酸残基）比细胞质中的短（约 250 个腺苷酸残基）。MTPAP 也可能催化多尿苷酸化。线粒体中的假尿苷化由线粒体假尿苷化模块催化，该模块包含尿苷酸合成酶 RPUSD3、RPUSD4 和 TRUB2。RPUSD4 对 rRNA 和 tRNA 进行假尿苷化，而 RPUSD3 或 TRUB2 则能假尿苷化 MT-CO1 mRNA 的尿苷酸-390 位点和 MT-CO3 mRNA 的尿苷酸-697 位点。RPUSD3 或 TRUB2 的缺失会导致线粒体翻译减少。线粒体中，mRNA 上腺苷残基 N1 位的甲酰化由甲基转移酶 TRMT61B 催化，该酶对 MT-ND1、MT-CO1、MT-CO2、MT-CO3、MT-ND4L 和 MT-CYB mRNA 上的腺苷酸残基进行甲酰化。线粒体 mRNA 中的 N1-甲基腺苷酸会导致核糖体停滞并降低翻译效率。
英文描述
Synthesis of Leukotrienes (LT) and Eoxins (EX) Leukotrienes (LTs) are biologically active molecules formed in response to inflammatory stimuli. They cause contraction of bronchial smooth muscles, stimulation of vascular permeability, and attraction and activation of leukocytes. LTs were discovered in 1938 and were termed the "slow release substance" (SRS) until their structures were determined in 1979 and they were then renamed to leukotrienes. LTs are derived from arachidonate through action by arachidonate 5-lipoxygenase (ALOX5). Cysteinyl leukotrienes (LTC4, LTD4, and LTE4) are generated as products derived from leukotriene A4 (LTA4). Eoxins are generated from leukotrienes (LTs) and resemble cysteinyl leukotrienes but have a different three-dimensional structure (Murphy & Gijon 2007, Hammarstrom 1983, MA.Claesson 2009, Vance & Vance 2008, Buczynski et al. 2009).
所含基因
20 个基因