Recombinogenic Effects of Suppressors of Position-Effect Variegation in Drosophila

Corresponding author: Gunter Reuter, Biologicum, Martin Luther University, D-06120 Halle, Weinbergweg 10, Germany., reuter{at}genetik.uni-halle.de (E-mail)

Communicating editor: T. C. KAUFMAN

Compact chromatin structure, induction of gene silencing in position-effect variegation (PEV), and crossing-over suppression are typical features of heterochromatin. To identify genes affecting crossing-over suppression by heterochromatin we tested PEV suppressor mutations for their effects on crossing over in pericentromeric regions of Drosophila autosomes. From the 46 mutations (28 loci) studied, 16 Su(var) mutations of the nine genes Su(var)2-1, Su(var)2-2, Su(var)2-5, Su(var)2-10, Su(var)2-14, Su(var)2-15, Su(var)3-3, Su(var)3-7, and Su(var)3-9 significantly increase in heterozygotes or by additive effects in double and triple heterozygotes crossing over in the ri-p^p region of chromosome 3. Su(var)2-2⁰¹ and Su(var)2-14⁰¹ display the strongest recombinogenic effects and were also shown to enhance recombination within the light-rolled heterochromatic region of chromosome 2. The dominant recombinogenic effects of Su(var) mutations are most pronounced in proximal euchromatin and are accompanied with significant reduction of meiotic nondisjunction. Our data suggest that crossing-over suppression by heterochromatin is controlled at chromatin structure as well as illustrate the possible effects of heterochromatin on total crossing-over frequencies in the genome.

This article has been cited by other articles:

				X. Lu, S. N. Wontakal, A. V. Emelyanov, P. Morcillo, A. Y. Konev, D. V. Fyodorov, and A. I. Skoultchi Linker histone H1 is essential for Drosophila development, the establishment of pericentric heterochromatin, and a normal polytene chromosome structure Genes & Dev., February 15, 2009; 23(4): 452 - 465. [Abstract] [Full Text] [PDF]

				H. K. Dooner and L. He Maize Genome Structure Variation: Interplay between Retrotransposon Polymorphisms and Genic Recombination PLANT CELL, February 1, 2008; 20(2): 249 - 258. [Abstract] [Full Text] [PDF]

				M. J. Vogel, L. Guelen, E. de Wit, D. P. Hupkes, M. Loden, W. Talhout, M. Feenstra, B. Abbas, A.-K. Classen, and B. van Steensel Human heterochromatin proteins form large domains containing KRAB-ZNF genes Genome Res., December 1, 2006; 16(12): 1493 - 1504. [Abstract] [Full Text] [PDF]

				C. F. Weil Finding the crosswalks on DNA PNAS, April 30, 2002; 99(9): 5763 - 5765. [Full Text] [PDF]