Position Effects and Variegation Enhancers in an Autosomal Region of DROSOPHILA MELANOGASTER
AUTOR(ES)
Henikoff, Steven
RESUMO
A dominant eye color mutation was found associated with a third chromosome inversion broken distally at or near the karmoisin (kar) locus in 87C and proximally within centric heterochromatin. Suppressibility of the mutant phenotype by an extra Y chromosome indicated that this was an example of dominant position-effect variegation. When heterozygous with deficiencies uncovering the kar locus, this inversion chromosome was found to be lethal unless a region in 87EF was also deleted. Extra Y chromosomes rescued inversion/deletion heterozygotes, while removal of the Y chromosome from heterozygous males deficient for the region in 87EF was lethal. Thus, a variegating lethal lies near the breakpoint in 87C, and a wild-type gene that enhances its variegation lies in 87EF. Furthermore, deletion of the region in 87EF was found to strongly suppress white-mottled-4 (wm4) variegation, while deletion of another region in 87BC suppressed less strongly. These results indicate that essential genes on autosomes are sensitive to position effects, and loci that enhance variegation, as defined by deficiency mapping, are very common.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1217818Documentos Relacionados
- Mutations of Zeste That Mediate Transvection Are Recessive Enhancers of Position-Effect Variegation in Drosophila Melanogaster
- Single-Locus Modification of Position-Effect Variegation in DROSOPHILA MELANOGASTER. I. White Variegation
- Histone Gene Multiplicity and Position Effect Variegation in DROSOPHILA MELANOGASTER
- Single-Locus Modification of Position-Effect Variegation in DROSOPHILA MELANOGASTER. II. Region 3c Loci
- Position-Effect Variegation at Several Closely Linked Loci in Drosophila Melanogaster