Identification and characterisation of the developmental expression pattern of tbx5b, a novel tbx5 gene in zebrafish
Identification and characterisation of the developmental expression pattern of tbx5b, a novel tbx5 gene in zebrafish
复制标题
DOI：
10.1016/j.gep.2009.11.003
复制
发表时间：
2010-01-01
影响因子：
1.2
通讯作者：
Minguillon, Carolina
中科院分区：
文献类型：
--
作者：
Albalat, Ricard;Baquero, Mireia;Minguillon, Carolina
Tbx 5是一种T-box转录因子，其在大多数脊椎动物谱系中具有特征，并且在各种胚胎结构的发育过程中广泛表达，包括心脏，眼睛和成对附属物的前组（四足动物前肢和鱼类胸鳍）。TBX 5的突变导致Holt-Oram综合征，这是一种常染色体显性人类“心手”病症，其特征在于上肢和心脏畸形。在斑马鱼中，tbx 5功能受损的胚胎显示胸鳍完全缺失，而心脏和眼睛的发育并没有受到如此严重的干扰。在这里，我们在斑马鱼中发现了一个新的tbx 5基因，我们称之为tbx 5 b。这个重复的基因存在于所有的硬骨鱼基因组中，其序列是可用的，这表明它是由鱼类进化过程中发生的硬骨鱼特异性基因组重复事件造成的。我们发现，tbx 5 b已经失去了特征前肢/胸鳍表达的tbx 5基因，但保留了眼睛和心脏的表达，部分重叠，其paradium，现在被称为tbx 5a。因此，tbx 5a和tbx 5 b在眼睛和心脏中的功能冗余可以解释在tbx 5a功能受损的鱼胚胎中这些器官发育期间观察到的轻度表型。(C)2009 Elsevier B. V.保留所有权利。
Tbx5 is a T-box transcription factor that has been characterised in most vertebrate lineages and is widely expressed during the development of various embryonic structures, including the heart, the eyes and the anterior set of paired appendages (tetrapod forelimbs and fish pectoral fins). Mutations in TBX5 cause Holt-Oram syndrome, an autosomal dominant human "heart-hand" condition characterised by upper limb and heart malformations. In zebrafish, embryos with compromised tbx5 function show a complete absence of pectoral fins, whereas heart and eye development are not so highly disturbed. Here, we identify a new tbx5 gene in zebrafish that we have called tbx5b. This duplicate gene is present in all teleost genomes whose sequence is available, suggesting it resulted from the teleost-specific genome duplication event that took place during fish evolution. We show that tbx5b has lost the characteristic forelimb/pectotal fin expression of Tbx5 genes but has retained the eye and heart expression, partially overlapping with that of its paralogue, now referred to as tbx5a. Functional redundancy of tbx5a and tbx5b in the eye and heart would therefore explain the mild phenotypes observed during development of these organs in fish embryos with compromised tbx5a function. (C) 2009 Elsevier B.V. All rights reserved.