%0 Journal Article %T Identification and characterization of bovine regulator of telomere length elongation helicase gene (RTEL): molecular cloning, expression distribution, splice variants and DNA methylation profile %A Zhuo Du %A DingSheng Zhao %A YongHui Zhao %A ShaoHua Wang %A Yu Gao %A Ning Li %J BMC Molecular Biology %D 2007 %I BioMed Central %R 10.1186/1471-2199-8-18 %X Here we report the cDNA cloning, genomic structure, chromosomal location, alternative splicing pattern, expression distribution and DNA methylation profile of the bovine homolog of RTEL. The longest transcript of bovine RTEL is 4440 nt, encompassing 24.8 kb of genomic sequence that was mapped to chromosome 13q2.2. It encodes a conserved helicase-like protein containing seven characterized helicase motifs in the first 750 aa and a PIP box in the C-terminus. Four splice variants were identified within the transcripts in both the coding and 5'-untranslated regions; Western blot revealed that the most abundant splice variant SV-1 was translated to a truncated isoform of RTEL. The different 5'UTRs imply alternative transcription start sites in the promoter; Bovine RTEL was transcribed at the blastocyst stage, and expression levels were highest in adult testis, liver and ovary. DNA methylation analysis of tissues that differed significantly in expression level indicated that relatively low DNA methylation is associated with higher expression.In this study, we have identified and characterized a bovine RTEL homolog and obtained basic information about it, including gene structure, expression distribution, splice variants and profile of DNA methylation around two putative transcription start sites. These data may be helpful for further comparative and functional analysis of RTEL in mammals.Telomeres are specialized nucleoprotein complexes that form the natural ends of eukaryotic chromosomes and have important structural and protective roles. Cellular telomere length, which undergoes dynamic changes and is stringently regulated by a series of telomere-associated proteins, is fundamental to the understanding of cell growth and survival, replicative life-span and carcinogenesis [1-3]. In recent years, several factors other than the well-known telomerase regulation pathway have been shown to regulate telomere length considerably [4]: oxidative damage [5,6] or mutation of the te %U http://www.biomedcentral.com/1471-2199/8/18