title: Interchromosomal recombination in Zea mays.
abstract: A new allele of the 27-kD zein locus in maize has been generated by interchromosomal recombination between chromosomes of two different inbred lines. A continuous patch of at least 11,817 bp of inbred W64A, containing the previously characterized Ra allele of the 27-kD zein gene, has been inserted into the genome of A188 by a single crossover. While both junction sequences are conserved, sequences of the two homologs between these junctions differ considerably. W64A contains the 7313-bp-long retrotransposon, Zeon-1. A188 contains a second copy of the 27-kD zein gene and a 2-kb repetitive element. Therefore, recombination results in a 7.3-kb insertion and a 14-kb deletion compared to the original S+A188 allele. If nonpairing sequences are looped out, 206 single base changes, frequently clustered, are present. The structure of this allele may explain how a recently discovered example of somatic recombination occurred in an A188/W64A hybrid. This would indicate that despite these sequence differences, pairing between these alleles could occur early during plant development. Therefore, such a somatically derived chimeric chromosome can also be heritable and give rise to new alleles.
authors.affiliation: Waksman Institute, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08855-0759, USA.
authors.forename: W
authors.initials: W
authors.lastname: Hu
authors.forename: M C
authors.initials: MC
authors.lastname: Timmermans
authors.forename: J
authors.initials: J
authors.lastname: Messing
mesh_terms: D000483:Alleles; D018745:Genome, Plant; D011995:Recombination, Genetic; D003313:Zea mays / Q000235:genetics*