Structural dissimilarity in insulin-like growth factor II genes of the rat and the human.
A comparison of insulin-like growth factor II(IGFII) genes revealed the lack in the rat genome of a transcriptional system identified in human IGFII gene, h1-h2-h3. Complete deletion was, however, restricted to the h1 region, while the h2 and h3 sequences were conserved in a nearly intact form and in a highly deviated one, respectively. Meanwhile, the human genome contained a region highly homologous to the rE1 sequence, a rat-specific leader exon. These results indicate that the IGFII genes of these species were derived from a common ancestral gene having, together with two other common leader exons, rE2 (h4) and rE3 (h4B), four leader exons, and that the human-specific leader exon h1 sequence was not newly acquired in the human genome but was deleted from the rat genome after speciation.
Ikejiri
K
K
Department of Biochemistry, Kyushu University, Fukuoka, Japan.
Endo
H
H
Yamamoto
M
M
D000818:Animals; D001483:Base Sequence; D005091:Exons; D005796:Genes; D006801:Humans; D007335:Insulin-Like Growth Factor II / Q000235:genetics*; D008969:Molecular Sequence Data; D051381:Rats; D015183:Restriction Mapping; D012689:Sequence Homology, Nucleic Acid; D014158:Transcription, Genetic
D007335:Insulin-Like Growth Factor II