Citogenética de morcegos da família Phyllostomidae em áreas de Cerrado no estado de Mato Grosso

Abstract

The Phyllostomidae family is the most abundant and diverse in the Neotropical region and the bats that compose it are the most studied in both ecological and cytogenetic aspects. Despite it, some gaps in cytogenetic studies are still detected and, this way, the present work aimed to analyze the karyotype of bats representative of this family, in order to broaden the knowledge regarding the cytogenetics of this important group of vertebrates. The species analyzed were captured in Cerrado of Mato Grosso and came from three different locations: Nova Xavantina, Chapada dos Guimarães and Sinop. The captures were made using mist nets. Chromosome preparations were obtained by direct preparation of the bone marrow and, for species that presented karyotype variations, a fragment of Cytochrome oxidase b (Cyt-b) gene was amplified to calculate the genetic distances between the individuals. The results obtained include three published scientific articles or in the process of being, which compose the three chapters of thesis shown here: (1) Application of differential staining techniques in Vampyrum spectrum (Linnaeus, 1758) (Phyllostomidae, Chiroptera, Mammalia); (2) Karyotypic variation in Lophostoma silvicolum and Tonatia bidens (Phyllostomidae, Chiroptera, Mammalia) and (3) Karyotypes of two species of Dermanura (Chiroptera, Phyllostomidae) from the Center-West of Brazil. The results of chapter 1 indicate that this is the first study about chromosomal banding in Vampyrum spectrum (2n = 30; NF = 56). In chapter 2, some intriguing karyotypic variations in Lophostoma silvicolum (2n = 34; NF = 60/62) and Tonatia bidens (2n = 25/26; NF = 40) are described. In Chapter 3, unpublished data are also presented for the species Dermanura anderseni (2n = 30; NF = 56) and Dermanura gnoma (2n = 30; NF = 56). The distribution pattern of heterochromatin constitutive revealed markings in pericentromeric regions of all chromosomes of the five species and interstitial markings in short arms of subtelocentric chromosomes. The nucleolus organizer regions were evidenced in a pair of chromosomes for four species, with the exception of D. anderseni, which presented the AgNORs in two pairs. FISH with probes for rDNAs confirmed the silver markings in T. bidens and V. spectrum. Telomeric markings were detected and visualized in the terminal portions of all chromosomes of L. silvicolum, T. bidens and V. spectrum. No sites were observed in positions that could suggest the occurrence of chromosome rearrangements. The fluorochrome CMA3 allowed the identification of multiple transverse bands in the karyotypes, favoring pairing of homologues in L. silvicolum and V. spectrum, and in the T. bidens species it was also possible to identify the involved chromosomes in the found chromosomal fusion. The intraspecific genetic distances for species that presented karyotypic variations (L. silvicolum and T. bidens) based on the Cyt-b gene sequence were low, suggesting that differences in karyotypes probably refer to chromosomal polymorphisms that require to be better explored.