Sequence, gene structure, and expression pattern of CTNNBL1, a minor-class intron-containing gene - Evidence for a role in apoptosis

Department of Anatomy, Case Western Reserve University, Cleveland, OH 44106, USA.
Genomics (Impact Factor: 2.79). 03/2003; 81(3):292-303. DOI: 10.1016/S0888-7543(02)00038-1
Source: PubMed

ABSTRACT We have identified and characterized a cDNA designated CTNNBL1 (catenin (cadherin-associated protein), beta-like 1) coding for a protein of 563 amino acids having predicted structural homology to beta-catenin and other armadillo (arm) family proteins. CTNNBL1 is expressed in multiple human tissues, and its sequence is conserved across widely divergent species. The human CTNNBL1 gene on chromosome 20q11.2 contains 16 exons spanning > 178 kb. Intron 4 is a minor-class intron bearing AT at the 5' splice site and AC at the 3' splice site. An acidic domain, as well as a putative bipartite nuclear localization signal, a nuclear export signal, a leucine-isoleucine zipper, and phosphorylation motifs are present in the protein sequence. Transient expression of CTNNBL1 in CHO cells results in localization to the nucleus and apoptosis. The rate of cell death was higher when cells were transfected with a carboxy-terminal fragment of CTNNBL1, suggesting that the apoptosis-inducing activity is a function of this region.

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    • "EST #58 showed 96% identity with a putative nuclear protein from Oryza sativa (Table 1), as well as with an EST isolated from an embryo library of Hordeum vulgare (accession number A143619). In particular, our cDNA fragment shared 77% identity (e-value of 2e À 04) with the CTNNBL1 (catenin caderin-associated protein blike 1, Jabbour et al., 2003) gene of Homo sapiens (accession number AAH36739), which encodes for a protein having predicted structural homology with b-catenin and other armadillo (arm) family proteins. This gene was designated PpArmadillolike (PpARM). "
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