Kretschmer, R., et al. 140
J. Biotec. Biodivers. v. 5, N.2: pp. 140-147 May 2014
Vol. 5, N.2: pp. 140-147, May, 2014
ISSN: 2179-4804
Journal of Biotechnology
and Biodiversity
Rafael Kretschmer , Vanusa Lilian Camargo de Lima , Letiane Nascimento da Ponte , Tiago Marafiga Degrandi , Lúcia do Canto Vinadé , Adriano Luis Schünemann , Analía Del Valle Garnero , Ricardo José Gunski
NOR- bearing as a plesiomorphic characteristic in Mimus saturninus (Passeriformes Mimidae)
ABSTRACT
The order Passeriformes is the largest group of species karyotyped among birds, however little is known about the cytogenetic of the Mimidae family, registering only karyology basic data (giemsa staining). The aim of this study was to analyze the chromosomal complement from the species Mimus saturninus by conventional staining and differential chromosome banding. Diploid number and chromosome morphology were determined, as well as the distribution pattern of constitutive heterochromatin (CBG-banding), GTG-banding andAgNOR staining (NORs). The Chalk-browed Mockingbird has 2n=80. The first and fourth pairs are submetacentric and the second, third and fifth are acrocentric. The remaining chromosomes pairs of the complement have telocentric morphology. The Z chromosome is submetacentric and the W is metacentric. CBG-banding showed positive staining in the pericentromeric region of most macrochromosomes and microchromosomes and also at Z chromosome, differently from W chromosome which appeared totally heterochromatic. The GTG-banding was similar to Gallus gallus and in other species which have already been GTG-banded. The NORs were identified in a pair of microchromosomes characterized by presenting a remarkable secondary constriction. This can be considered as a plesiomorphic characteristic for M. saturninus once baseline groups (Paleognathae) also showed a pair of microchromosomes bearing NORs.
Key words: karyotype, macro and microchromosomes, chromosome banding.
*Autor para correspondência
1
Universidade Federal do Pampa, Rio Grande do Sul – Brasil. *email rafa.kretschmer@hotmail.com