Abstract
The genomic copy multiplicity of the CCAAT transcription complex component enhancer factor I subunit A (EFI A) has been examined. When a mammalian genomic Southern blot was hybridized to a rat EFI A cDNA, a complex pattern consisting of numerous related sequences was found in all the species examined, with Bos taurus being the least complex. An EFI A #1 cDNA from Bos taurus was isolated from a primary lung endothelial cell cDNA library by screening with the 1489-bp rat EFI A cDNA. The deduced bovine EFI A #1 amino acid (aa) sequence is 98% identical to rat EFI A and 100% identical to human EFI A /DbpB/YB-1 family member DNA-binding protein B (DbpB). In addition, a processed EFI A pseudogene from Bos taurus, designated bovine Ψ EFI A#1 , was obtained from a genomic library by screening with a rat EFI A cDNA probe. The bovine ΨEFI A#1 gene has an ORF which, if expressed, would encode a 140-aa sequence, with aa 31–140 having 84% identity to bovine EFI A#1 . The genomic cloning data indicate that processed pseudogenes are partially responsible for the complexity of the EFI A genomic Southern blots. The phenomenon of ‘repeat induced point mutation’ ( ripping) at bovine ΨEFI A#1 gene CpG dinucleotides occurs at a 6.5-fold higher frequency than expected from random mutagenesis. Therefore, ripping is likely to be the mechanism by which the bovine EFI A#1 pseudogene's ectopic recombination potential was inactivated.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
