Cloning and expression of a novel human gene, Isl-2, encoded a LIM-homeodomain protein.
The LIM-homeodomain (LIM-HD) proteins have a homeodomain and two N-terminal LIM domains, which consist of a conserved cysteine- and histidine-rich structure of two tandem repeated zinc fingers. LIM domain is involved in protein-protein interactions during transcriptional regulation. LIM-HD proteins are classically suggested as major transcriptional regulators which, in cooperation with other transcription factors, play critical roles in several developing systems and organs, such as nervous system, pancreas, and heart. Here we have cloned the full-length cDNA of human Isl-2 from a human embryo heart cDNA library. The gene contains six exons and spans 5.7 kb in chromosome 15q23 region, and transcribes a 1.9 kb mRNA that encodes a protein with 359 amino acid residues. The predicted protein, containing two tandem LIM motifs in N-terminal and a homeodomain domain, is well conserved, especially in the LIM and DNA-binding domains. Northern blot analysis shows that human Isl-2 is expressed in every human tissue examined at adult stage and during embryonic developmental stages from 34 days to 24 weeks at different levels in tissues. The broad expression of Isl-2 gene in tissues during embryogenesis and adult development suggests that it may be involved in both differentiation and maintenance of these tissues and might play an important role.
Li
Yongqing
Y
Center for Heart Development, Key Laboratory of MOE for Development Biology and Protein Chemistry, College of Life Sciences, Hunan Normal University, Changsha, 410081, Hunan, People's Republic of China.
Zhang
Yuejuan
Y
He
Bei
B
Wang
Yuequn
Y
Yuan
Zengjin
Z
Yuan
Wuzhou
W
Liao
Peng
P
Deng
Yun
Y
Xiao
Jing
J
Zhu
Chuanbing
C
Wang
Ying
Y
Wu
Xiushan
X
Liu
Mingyao
M
D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D004622:Embryo, Mammalian; D047108:Embryonic Development / Q000235:genetics; D015870:Gene Expression; D005865:Gestational Age; D018398:Homeodomain Proteins / Q000235:genetics; D006801:Humans; D060850:LIM-Homeodomain Proteins; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000235:genetics* / Q000378:metabolism; D010802:Phylogeny; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D014018:Tissue Distribution; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism
D018398:Homeodomain Proteins; C516210:ISL2 protein, human; D060850:LIM-Homeodomain Proteins; D009419:Nerve Tissue Proteins; D014157:Transcription Factors