Inactivation of the H-2Klk gene could involve the substitutions of methylated CpGs.
By the isolation of overlapping cosmid clones and 'chromosome walking' studies from the H-2Kk gene, we have obtained cosmid clones encoding the H-2Klk gene from two separate cosmid libraries. The nucleotide sequence of one of the clones was determined. The cloned H-2Klk gene could be transcribed in vitro to give a normal H-2 class I mRNA of 1.7 kb. However, the deletion of four nucleotides in exon 3 of the H-2Klk gene results in a translation termination codon at the beginning of exon 4. In agreement with this, when expressed in human cells, the H-2Klk gene gave a truncated, cytoplasmic polypeptide of Mr 36,000. Therefore, although the H-2Klk gene is homologous to other class I MHC genes in its molecular organization and nucleotide sequence, it is a pseudogene. When compared to the nucleotide sequence of the H-2Kk gene, the H-2Klk gene has undergone many substitutions of methylated CpG residues (meCpG). This represents further evidence to suggest that this gene is inactive.
|Keywords||*Genes, MHC Class I, 0 (Cosmids), 0 (H-2 Antigens), Amino Acid Sequence, Animals, Base Sequence, Chromosome Mapping, Chromosome Walking, Cloning, Molecular, Cosmids, H-2 Antigens/*genetics, Linkage (Genetics), Methylation, Mice, Molecular Sequence Data, Mutation, Support, Non-U.S. Gov't|
Sim, B.C., Grosveld, F.G., & Hui, K.M.. (1990). Inactivation of the H-2Klk gene could involve the substitutions of methylated CpGs.. Journal of Immunogenetics, 17, 133–150. Retrieved from http://hdl.handle.net/1765/2457