A variable intron distribution in globin genes of Chironomus: evidence for recent intron gain

doi:10.1016/S0378-1119(97)00518-0

Gene

Volume 205, Issues 1–2, 31 December 1997, Pages 151-160

https://doi.org/10.1016/S0378-1119(97)00518-0 Get rights and content

Abstract

The intron positions found in globin genes of plants, protozoa and invertebrates have been interpreted as evidence for a threeintron-four-exon structure of the ancestral globin gene. In particular, the so-called ‘central’ introns, which are not found in vertebrate globin genes but are present in a variety of invertebrate and plant species, have been used as an argument for an ancestral gene structure featuring three introns. We have analyzed the presence or absence of central introns in the Gb genes 2β, 9 and 7A of various European and Australasian species of the insect Chironomus. We find unrelated central introns at different positions in some of the species investigated, while other species completely lack introns in these genes. This variable distribution of introns is parsimoniously explained by independent intron additions. Such a gain of introns may occur convergently at identical positions in unrelated taxa. Insertion by gene conversion may be a viable mechanism to explain intron gain.

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A variable intron distribution in globin genes of Chironomus: evidence for recent intron gain

Abstract

Gene

Cell

Curr. Biol.

Gene

Curr. Opin. Genet. Dev.

Curr. Opin. Genet. Dev.

FEBS Lett.

Cell

Trends Genet.

Cell

J. Mol. Biol.

Curr. Biol.

Comp. Biochem. Physiol.

Intron-less globin genes in the insect Chironomus thummi thummi

Nature

The chimeric nature of nuclear genomes and the antiquity of introns as demonstrated by the GAPDH gene system

Nuclear genes encoding chloroplast hemoglobins in the unicellular green alga Chlamydomonas eugametos

Mol. Gen. Genet.

A role for reverse transcripts in gene conversion

Nature

Evidence that introns arose at protosplice sites

EMBO J.

Did the ancestral globin gene of plants and animals contain only two introns?

Trends Biochem. Sci.

Phylogenies from molecular sequences: inference and reliability

Ann. Rev. Genet.

Intron loss from the NADH dehydrogenase subunit 4 gene of lettuce mitochondrial DNA: evidence for homologous recombination of a cDNA intermediate

Mol. Gen. Genet.

Correlation of DNA exonic regions with protein structural units in haemoglobin

Nature

The analysis of a protein polymorphism

An evolutionary tree for invertebrate globin sequences

J. Mol. Evol.

Cotransposition of a highly repetitive DNA element with flanking sequences in the genome of the midge Chironomus thummi

J. Mol. Evol.

Molekulare Analyse phylogenetisch bedeutsamer repetitiver DNA bei Chironomiden

Complete nucleotide sequence of a hemoglobin gene cluster from the midge Chironomus thummipiger

Transposition of minisatellite-like DNA in Chironomus midges

Genome