Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “pseudogene”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,135 records · Page 63Linked to original sources

Pseudogenes.

Explore the source record for details and available documents.

Animals↗

Structure of the human immunoglobulin C epsilon 2 gene, a truncated pseudogene: implications for its evolutionary origin.

Cloning of the overlapping DNA fragments together with Southern hybridization experiments showed the organization of the human C epsilon and C alpha gene cluster as 5'-C epsilon 2-14 kilobases-C alpha 1----C epsilon 1-13 kilobases-C alpha 2-3'. Comparison of the nucleotide sequences of the C epsilon 1 and C epsilon 2 genes revealed that four deletions have taken place in the C epsilon 2 gene and its flanking regions. The three deleted regions in the 5' side of the C epsilon 2 gene are partially filled with shorter inserted sequences. One of them has removed the CH1 and CH2 exons and a portion of the epsilon switch (S epsilon) region. The S epsilon region and the CH4 exon still retain the functional structures, whereas the CH3 exon has been inactivated by deleting its 5' intervening sequence necessary for splicing. The tetranucleotide T-G-G-G (or T-G-G-C), which is usually found in close proximity of the class-switch recombination sites in mouse myelomas, is located 5' to the three deletion sites. The results imply that the mechanism responsible for the heavy chain class-switch recombination might be relevant to the evolutionary mechanism of creation of the truncated C epsilon 2 gene. The other deletion in the 3' flanking region of the C epsilon 2 gene may be due to slipped mispairing of the short direct repeat (C-C-C-C-C) at both ends.

Base Sequence↗

Complete nucleotide sequence of two steroid 21-hydroxylase genes tandemly arranged in human chromosome: a pseudogene and a genuine gene.

Two 21-hydroxylase [P-450(C21)] genes have been isolated from a human genomic library using a bovine P-450(C21) cDNA. The insert DNAs containing the P-450(C21) genes were also hybridized with the sequences of the 5' or 3' end regions of human C4 cDNA, indicating a close linkage of the P-450(C21) gene to the C4 gene. Sequence analysis has revealed that the two P-450(C21) genes are both approximately equal to 3.4 kilobases long and split into 10 exons. Comparing the two sequences, we found that the two genes are highly homologous including their introns and flanking sequences, but that three mutations render one of the two P-450(C21) genes nonfunctional--1 base insertion, an 8-base deletion, and a transition mutation--all of which may cause premature termination of the translation. Tandem arrangement of the highly homologous pseudo- and genuine genes in close proximity could account for the high incidence of P-450(C21) gene deficiency by homologous gene recombination.

Base Sequence↗

Characterization of three chicken pseudogenes for U1 RNA.

Three chicken genomic DNA clones containing the U1 RNA sequence were isolated from a chicken gene library and characterized. Two of these clones, CL64 and CL111, are overlapping clones which show several single-nucleotide changes in the U1 coding sequence, suggesting that they probably are alleles of the same sequence. The U1 sequence in the third clone, CL40, is more divergent. Flanking regions of these genes do not share any sequence homology between each other or with the previously isolated chicken genomic clone CL59. A short repeat CGGGG appears 28 times upstream of the U1 sequence in CL59. Another repeat, GCACC, is repeated 14 times upstream of the U1 region in CL40.

Animals↗

Characterization of a rat tRNA gene cluster containing the genes for tRNAAsp, tRNAGly and tRNAGlu, and pseudogenes.

The putative genes for tRNAGAUAsp(C), tRNAGGAGly(G) and tRNAGAGGlu are in a cluster on the rat chromosome and are present exclusively in a 3.3 kb region cleaved with a restriction endonuclease EcoRI. The cluster reiterates about 10 times on the haploid DNA. Four lambda clones each containing an independent repeating unit were isolated from a rat gene library. The studies on the cloned DNA revealed that the length of the repeating unit including the 3.3 kb EcoRI fragment was at least 13.5 kb. Nucleotide sequence analysis of the 3.3 kb DNA in the isolated clones showed sequence variations among the repeating units and incomplete genes for tRNAGly and tRNAGlu within the clusters.

Animals↗