Three decades of studies on chromosomal polymorphism of Drosophila willistoni and description of fifty different rearrangements

Genetics and Molecular Biology

Claudia Rohde¹  Vera Lúcia S. Valente¹ 

[1] ,Universidade Federal do Rio Grande do Sul Instituto de Biociências Departamento de GenéticaPorto Alegre RS ,Brazil

关键词: cytogenetic;    polytene chromosomes;    inversions;    Drosophila willistoni;   

DOI  :  10.1590/S1415-47572012000600012

来源: SciELO

【 摘 要 】

Drosophila willistoni (Insecta, Diptera) is considered a paradigm for evolutionary studies. Their chromosomes are characterized by multiple paracentric inversions that make it hard to identify and describe chromosomal poly-morphisms. In the present report we attempted to systematize the description of all the 50 inversions found in the last three decades, since we have been studying the chromosomes of several individuals of 30 different populations, including the one used in the genome sequencing project (Gd-H4-1). We present the photographic register of 11 arrangements in the left arm of the X chromosome (XL), eight in the right arm (XR), 10 in the left arm of chromosome II (IIL), eight in its right arm (IIR) and 13 in chromosome III. This information also includes their breakpoints on the reference photomap. A clear geographic difference was detected in XL and XR, with different fixed arrangements depending on the origin of the population studied. Through the comparison of all X arrangements it was possible to infer the putative ancestral arrangements, i.e., those related to all the remaining arrangements through the small number of inversions that occurred in the past, which we will call XL-A and XR-A. In the autosomes (IIL/IIR and III), fixed inversions were detected, but most are segregating in different frequencies along the geographical distribution of the D. willistoni populations.

【 授权许可】

CC BY   
 All the contents of this journal, except where otherwise noted, is licensed under a Creative Commons Attribution License