title: Tandem duplication of alkaline phosphatase genes and polymorphism in the intergenic sequence in Bombyx mori.
abstract: Alkaline phosphatases are ubiquitous in organisms from bacteria to human. Two alkaline phosphatase genes, Alp-m and Alp-s, were independently cloned from the silkworm Bombyx mori. They were mapped to a small DNA region and shown to be organized in tandem. Exon-intron structures of the two genes were highly conserved, with the exception of the second intron in Alp-m, which has no counterpart in Alp-s. The similarity between the nucleotide sequences of the exons of the two genes was strikingly high (60-79%), suggesting that Alp-m and Alp-s originated from a duplication of their common ancestor gene. The intergenic sequence between the two Alp genes shows length polymorphism in different B. mori strains, which can be explained by presence/absence of two putative insertion sequences. This structural variation suggests a possible scenario for the divergence of the two Alp genes after the duplication event.
mesh_terms: D000469:Alkaline Phosphatase / Q000235:genetics*; D000818:Animals; D001483:Base Sequence; D012831:Bombyx / Q000201:enzymology* / Q000235:genetics*; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics; D019143:Evolution, Molecular; D005091:Exons; D020440:Gene Duplication; D017344:Genes, Insect; D007438:Introns; D005810:Multigene Family; D011110:Polymorphism, Genetic
chemical_list: D004247:DNA; D000469:Alkaline Phosphatase