Field-collected specimens of all known taxa in the Anopheles gambiae complex were analyzed on the basis of chromosome inversions with reference to a standard polytene chromosome map. The phylogenetic relationships among the seven described species in the complex could be inferred from the distribution of fixed inversions. Nonrandom patterns of inversion distribution were observed and, particularly on chromosome arm 2R, provided evidence for genetically distinct populations in A. gambiae, A. arabiensis, and A. melas. In A. gambiae from Mali, stable genetic differentiation was observed even in populations living in the same region, suggesting a process of incipient speciation which is being confirmed by studies with molecular markers. The possible role of chromosome differentiation in speciation of the A. gambiae complex and in the emergence of distinct chromosomal forms within the nominal species is discussed in relation to human malaria.
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http://dx.doi.org/10.1126/science.1077769 | DOI Listing |
Based on the morphology of the polytene chromosomes, 21 species of the genus Chironomus Meigen from Bulgaria have been identified. Original pictures of the polytene chromosomes are presented for each species. "Basic" sequences were determined for each arm of the polytene chromosomes which are used to determine the corresponding arms of the chromosomes, and the cytocomplex to which the species belongs.
View Article and Find Full Text PDFThe polytene chromosomes, larva, pupa, and male are described for the black fly Simulium chaouikaidi n. sp., a member of the Simulium venustum group from Morocco.
View Article and Find Full Text PDFPLoS One
October 2024
Department of Biological Sciences, University of South Alabama, Mobile, Alabama, United States of America.
Invasive species are a threat to ecosystems worldwide, but determining if a species is adventive or native is not always straightforward. The black flies that inhabit the Galapagos Islands, long known as Simulium ochraceum, are blood-feeding pests of humans and livestock. They first came to the attention of residents in 1989, suggesting a recent arrival.
View Article and Find Full Text PDFActa Trop
November 2024
International Center for Island Studies, Kagoshima University, Korimoto 1-21-24, Kagoshima, Japan.
Dokl Biol Sci
October 2024
Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia.
The transcription factor Z4 (putzig) is one of the key proteins that determine the chromatin structure in Drosophila. Z4 is found at the boundaries of bands on polytene chromosomes, and the bands are currently thought to correlate with chromatin domains. Z4 is a component of a protein complex that additionally includes Chromator and BEAF-32, and a conserved domain is necessary to occur at the N end of Z4 to ensure its interaction with the two proteins.
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