Sequence, gene structure, and expression pattern of CTNNBL1, a minor-class intron-containing gene - Evidence for a role in apoptosis
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.
- SourceAvailable from: Emidio Albertini
[Show abstract] [Hide abstract]
- "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). "
ABSTRACT: The essential feature of apomixis is that an embryo is formed autonomously by parthenogenesis from an unreduced egg of an embryo sac generated through apomeiosis. The genetic constitution of the offspring is, therefore, usually identical to the maternal parent, a trait of great interest to plant breeders. If apomixis were well understood and harnessed, it could be exploited to indefinitely propagate superior hybrids or specific genotypes bearing complex gene sets. A fundamental contribution to the understanding of the genetic control of the apomictic pathway could be provided by a deep knowledge of molecular mechanisms that regulate the reproductive events. In Poa pratensis the cDNA-AFLP method of mRNA profiling allowed us to visualize a total of 2248 transcript-derived fragments and to isolate 179 sequences that differed qualitatively or quantitatively between apomictic and sexual genotypes at the time of flowering when the primary stages of apomixis occur. Three ESTs were chosen for further molecular characterization because of their cDNA-AFLP expression pattern and BLAST information retrieval. The full-lengths of the newly isolated genes were recovered by RACE and their temporal expression patterns were assessed by RT-PCR. Their putative role in cell signaling transduction cascades and trafficking events required during sporogenesis, gametogenesis and embryogenesis in plants is reported and discussed.Plant Molecular Biology 12/2005; 56(6):879-94. DOI:10.1007/s11103-004-5211-y · 4.07 Impact Factor
[Show abstract] [Hide abstract]
- "AAK27389.1). Recently, this protein has been renamed CT- NNBL1, and, of interest, it has been found to induce apoptosis when expressed in Chinese hamster ovary cells (Jabbour et al., 2003). Our data suggest that this protein also has an important role as a negative regulator of cell death at least in Xenopus development. "
ABSTRACT: The diploid frog X. tropicalis has recently been adopted as a model genetic system, but loss-of-function screens in Xenopus have not yet been performed. We have undertaken a pilot functional knockdown screen in X. tropicalis for genes involved in nervous system development by injecting antisense morpholino (MO) oligos directed against X. tropicalis mRNAs. Twenty-six genes with primary expression in the nervous system were selected as targets based on an expression screen previously conducted in X. laevis. Reproducible phenotypes were observed for six and for four of these, a second MO gave a similar result. One of these genes encodes a novel protein with previously unknown function. Knocking down this gene, designated pinhead, results in severe microcephaly, whereas, overexpression results in macrocephaly. Together with the early embryonic expression in the anterior neural plate, these data indicate that pinhead is a novel gene involved in controlling head development.Developmental Dynamics 02/2004; 229(2):289-99. DOI:10.1002/dvdy.10440 · 2.67 Impact Factor
- [Show abstract] [Hide abstract]
ABSTRACT: To identify genetic alterations underlying rectal carcinogenesis, we used global gene expression profiling of a series of 17 locally advanced rectal adenocarcinomas and 20 normal rectal mucosa biopsies on oligonucleotide arrays. A total of 351 genes were differentially expressed (P < 1.0e-7) between normal rectal mucosa and rectal carcinomas, 77 genes had a >5-fold difference, and 85 genes always had at least a 2-fold change in all of the matched samples. Twelve genes satisfied all three of these criteria. Altered expression of genes such as PTGS2 (COX-2), WNT1, TGFB1, VEGF, and MYC was confirmed, whereas our data for other genes, like PPARD and LEF1, were inconsistent with previous reports. In addition, we found deregulated expression of many genes whose involvement in rectal carcinogenesis has not been reported. By mapping the genomic imbalances in the tumors using comparative genomic hybridization, we could show that DNA copy number gains of recurrently aneuploid chromosome arms 7p, 8q, 13q, 18q, 20p, and 20q correlated significantly with their average chromosome arm expression profile. Taken together, our results show that both the high-level, significant transcriptional deregulation of specific genes and general modification of the average transcriptional activity of genes residing on aneuploid chromosomes coexist in rectal adenocarcinomas.Cancer Research 01/2006; 66(1):267-82. DOI:10.1158/0008-5472.CAN-05-2533 · 9.28 Impact Factor