Neuroscience Centre, Institute of Cell and Molecular Science, Barts and The London School of Medicine and Dentistry, Queen Mary, University of London, 4 Newark Street, Whitechapel, London E1 2AT, United Kingdom.
Genome. 2009 Nov;52(11):968-74. doi: 10.1139/g09-061.
The Mpv17l protein has two isoforms, M-LPL and M-LPS, which both regulate the production of reactive oxygen species (ROS) and protect against mitochondrial oxidative stress and apoptosis. M-LPL is ubiquitously expressed, while M-LPS is expressed mostly in the kidney of aged animals. We identified a variety of transcripts of the Mpv17l gene that could encode novel isoforms by mapping expressed sequence tags on the mouse M-LP genomic locus. We analysed the expression and evolutionary conservation of a novel Mpv17l transcript (mpv17l-002) that is predicted to encode a new protein, termed M-LP2. The isoform M-LP2 has the full length of M-LPS plus six amino acids at the end of its amino terminus, which could be encoded by an alternative 5'-flanking sequence. We show that the mRNA of M-LP2 has a different pattern of expression than the mRNA of M-LPS, and sequences of both transcripts are conserved in the rodent genome; however, neither of these isoforms is detected in the human genome. These observations suggest that the functions of certain M-LP isoforms are tissue- and species-specific, implying that their potential involvement in ROS metabolism may be redundant or may be complemented by other members of the Mpv17 family.
Mpv17l 蛋白有两种异构体，M-LPL 和 M-LPS，它们都能调节活性氧（ROS）的产生，保护线粒体免受氧化应激和凋亡。M-LPL 广泛表达，而 M-LPS 主要在老年动物的肾脏中表达。我们通过在小鼠 M-LP 基因组基因座上定位表达序列标签，鉴定了 Mpv17l 基因的多种转录本，这些转录本可能编码新的异构体。我们分析了一种新的 Mpv17l 转录本（mpv17l-002）的表达和进化保守性，该转录本预测编码一种新的蛋白质，称为 M-LP2。异构体 M-LP2 具有 M-LPS 的全长和其氨基末端的六个氨基酸，这可能由一个替代的 5'侧翼序列编码。我们表明，M-LP2 的 mRNA 的表达模式与 M-LPS 的 mRNA 不同，并且这两个转录本的序列在啮齿动物基因组中保守；然而，在人类基因组中都没有检测到这些异构体。这些观察结果表明，某些 M-LP 异构体的功能具有组织和物种特异性，这意味着它们在 ROS 代谢中的潜在作用可能是冗余的，或者可能被 Mpv17 家族的其他成员所补充。
