TY - JOUR TI - A new gene in Drosophila melanogaster, Ravus, the phantom of the modifier of position-effect variegation Su(var)3-7. AU - Delattre, Marion AU - Spierer, Anne AU - Hulo, Nicolas AU - Spierer, Pierre T2 - The International Journal of Developmental Biology AB - In a search for homologues of the dominant modifier of position-effect variegation Su(var)3-7, we have identified one ORF in Drosophila melanogaster. The 359 amino acid deduced protein is much shorter than the 1169 amino acid protein Su(var)3-7. Surprisingly, the two genes are very close to each other at 87E on the polytene chromosome map, and are transcribed divergently. The triplet coding for the N-terminus amino acid of the new gene lies only 368 base pairs from the start of transcription of Su(var)3-7. This opposite orientation of the homologue has led us to name it Ravus. The N-terminus of the Ravus protein contains only one of the seven unusual zinc fingers of Su(var)3-7. A second region of similarity encodes an acidic domain. Finally, there is a block of high similarity near the C-terminus of the two proteins. It corresponds to a new conserved protein domain, BESS, found also in the BEAF and Stonewall Drosophila proteins. We have constructed a tagged Ravus protein, and have expressed it as a heat-shock inducible transgene. Ravus associates in vivo with polytene chromosomes but, in contrast to the heterochromatin-associated protein Su(var)3-7, does not show specificity for the chromocenter. Ravus does not seem either to modify the genomic silencing of position-effect variegation, as over-expression of the transgene does not affect the variegated phenotype of a number of rearrangements tested. PY - 2002 VL - 46 IS - 1 SP - 167 EP - 171 J2 - Int. J. Dev. Biol. LA - en SN - 0214-6282 SN - 1696-3547 UR - https://ijdb.ehu.eus/article/11902679 Y2 - 2024/11/24/18:15:37 ER -