期刊
HUMAN MOLECULAR GENETICS
卷 14, 期 5, 页码 585-593出版社
OXFORD UNIV PRESS
DOI: 10.1093/hmg/ddi055
关键词
-
Persistent truncus arteriosus (PTA) is a failure of septation of the cardiac outflow tract (OFT) into the pulmonary artery and the aorta. A common arterial trunk (CAT) is often diagnosed as PTA in the absence of evidence of embryological mechanism. We have used autozygosity mapping of a large consanguineous family segregating CAT to map the causative locus to chromosome 8p21. An F151L mutation was identified in the homeodomain of NKX2.6, a transcription factor expressed in murine pharyngeal endoderm and embryonic OFT myocardium. Although expression of Nkx2.6 during murine embryogenesis is strongly suggestive of a role for this gene in heart development, mice homozygous for a targeted mutation of Nkx2.6 are normal. However, in these mice, it has been shown that Nkx2.5 expression expands into regions lacking Nkx2.6, suggesting functional complementation. As transcriptional targets of NKX2.6 are unknown, we investigated functional effects of the mutation in transcriptional and protein interaction assays using NKX2.5 as a surrogate. Introduction of F157L into human NKX2.5 substantially reduced its transcription activating function, its synergism with partners at the atrial natriuretic factor (ANF) and connexin-40 (Cx40) promoters and its specific DNA binding. We tested NKX2.5 target promoters for NKX2.6 activity. NKX2.6 was inactive at ANF but weakly activated transcription of a Cx40 promoter, whereas the F151L mutant lacked this activity. These findings indicate a previously unsuspected role for NKX2.6 in heart development, which should be re-evaluated in more sophisticated model systems.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据