CYTOGENETIC ANALYSES OF SATELLITE DNA PcP190 AND AG-NOR SITES REVEAL INTERPOPULATION VARIATION IN SPECIES OF THE GROUP PHYSALAEMUS GRACILIS (ANURA, LEPTODACTYLIDAE)

PACHECO MOSQUINI PH; FERRO JM; LOURENÇO LB

Frei Caneca

Congreso; XXII Congreso Brasileiro de Biologia Molecular; 2024

The group Physalaemus gracilis comprises six species. Cytogenetic analyses of this group have beenrestricted to karyotype descriptions for P. barrioi, P. carrizorum, P. gracilis, and P. lisei, and chromosomemapping of PcP190 satellite DNA (satDNA) for the latter three. PcP190 satDNA has been found in sevenfamilies of the Hyloidea superfamily, emerging as a valuable chromosomal marker in comparativecytogenetic analyses in anurans, along with the nucleolar organizing regions (NORs). To deepen thestudy of this group, we mapped the PcP190 satDNA to the karyotypes of P. barrioi, P. evangelistai, anda new population of P. carrizorum (Palmas-PR). Additionally, we localized the Ag-NORs sites in P.evangelistai and P. carrizorum karyotypes. Chromosome preparations obtained from intestine and testiswere hybridized with PcP190 satDNA probes labeled with digoxigenin-12-dUTP, and silver-impregnatedusing the Ag-NOR method. Chromosomal clusters of PcP190 satDNA were detected associated withconstitutive heterochromatin in (peri)centromeric regions of the short arm of chromosome 1 in P.evangelistai and the long arm of chromosome 1 and short arm of chromosome 3 in P. barrioi and P.carrizorum. NORs were found terminally and interstitially in the long arm of chromosome 8 in P.carrizorum and P. evangelistai, respectively. The locations of NORs and chromosomal clusters ofPcP190 satDNA found in P. carrizorum were different from those reported in the literature for P.carrizorum from Misiones-Argentina. These results indicate that further analyses of these species offrogs are needed, since the existence of undescribed species within this group should not bedisregarded.