Rescue from oculocutaneous albinism type 4 using medaka slc45a2 cDNA driven by its own promoter
Rescue from oculocutaneous albinism type 4 using medaka slc45a2 cDNA driven by its own promoter
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DOI：
10.1534/genetics.107.073387
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发表时间：
2008-02-01
期刊：
影响因子：
3.3
通讯作者：
Mitani, Hiroshi
中科院分区：
文献类型：
--
作者：
Fukamachi, Shoji;Kinoshita, Masato;Mitani, Hiroshi
患有眼皮肤白化病4型(OCA4)的患者和脊椎动物突变体具有溶质携带者家族45成员2(SLC45A2)基因突变。然而，没有经验证据证明这种基因-表型关系。在青竹(B)中有一种独特的OCA4突变体，它只在皮肤上表现出白化病，但这种表型的机制也不清楚。在这项研究中，我们通过显微注射含有SLC45A2的基因组片段或由其自身0.9kb启动子驱动的SLC45A2基因来拯救青竹OCA4在眼睛和皮肤中的表型。我们还发现启动子中339bp的自发核苷酸突变是b突变。青竹SLC45A2有多个转录起始点，就像它的人类同源基因一样，只有最短的和眼睛特异的mrna与b突变一起转录。有趣的是，我们进一步通过青蛙-河豚比较基因组学揭示了启动子中一个类似于10bp的富含嘧啶(Py)的保守序列，并证实了它对SLC45A2在皮肤中的表达起着不可或缺的作用。对本研究中确定的0.9kb启动子的进一步研究将有助于深入了解SLC45A2眼睛和皮肤表达的顺式/反式调节机制。
Patients and vertebrate mutants with oculocutaneous albinism type 4 (OCA4) have mutations in the solute carrier family 45 member 2 (slc45a2) gene. However, there is no empirical evidence for this gene-phenotype relationship. There is a unique OCA4 mutant in medaka (b) that exhibits albinism only in the skin, but the mechanism underlying this phenotype is also unknown. In this study, we rescued medaka OCA4 phenotypes, in both the eyes and the skin, by micro-injection of an slc45a2-containing genomic fragment or slc45a2 cDNA driven by its own 0.9-kb promoter. We also identified a spontaneous nucleotide change of 339 bp in the promoter as the b mutation. There are multiple transcription start sites in medaka slc45a2, as in its human ortholog, and only the shortest and eye-specific mRNA is transcribed with the b mutation. Interestingly, we further revealed a conserved pyrimidine (Py)-rich sequence of similar to 10 bp in the promoter by medaka-pufferfish comparative genomics and verified that it plays an indispensable role for expression of slc45a2 in the skin. Further studies of the 0.9-kb promoter identified in this study should provide insights into the cis/trans-regulatory mechanisms underlying the ocular and cutaneous expression of slc45a2.