Comparative analysis based on replication banding reveals the mechanism responsible for the difference in the karyotype constitution of treefrogs Ololygon and Scinax (Arboranae, Hylidae, Scinaxinae)

Abstract

Citation: Gruber SL, de Oliveira GIG, Silva APZ, Narimatsu H, Haddad CFB, Kasahara S (2017) Comparative analysis based on replication banding reveals the mechanism responsible for the difference in the karyotype constitution of treefrogs Ololygon and Scinax (Arboranae, Hylidae, Scinaxinae). Comparative Cytogenetics 11(2): 267-283. https://doi. org/10.3897/CompCytogen.11(2).11254 Abstract According to the recent taxonomic and phylogenetic revision of the family Hylidae, species of the former Scinax catharinae (Boulenger, 1888) clade were included in the resurrected genus Ololygon Fitzinger, 1843, while species of the Scinax ruber (Laurenti, 1768) clade were mostly included in the genus Scinax Wagler, 1830, and two were allocated to the newly created genus Julianus Duellman et al., 2016. Although all the species of the former Scinax genus shared a diploid number of 2n = 24 and the same fundamental number of chromosome arms of FN = 48, two karyotypic constitutions were unequivocally recognized, related mainly to the distinct size and morphology of the first two chromosome pairs. Some possible mechanisms for these differences had been suggested, but without any experimental evidence. In this paper, a comparison was carried out based on replication chromosome banding, obtained after DNA incorporation of 5-bromodeoxiuridine in chromosomes of Ololygon and Scinax. The obtained results revealed that the loss of repetitive segments in chromosome pairs 1 and 2 was the mechanism responsible for karyotype difference. The distinct localization of the nucleolus organizer regions in the species of both genera also differentiates the two karyotypic constitutions. Simone Lilian Gruber et al. / Comparative Cytogenetics 11(2): 267-283 (2017) 268

Repetitive DNA Mapping in Five Genera of Tree Frogs (Amphibia: Anura) from the Atlantic Forest: New Highlights on Genomic Organization in Hylidae

“…Furthermore, the morphological differentiation of the first two chromosomal pairs and the distribution of microsatellites between the genera Ololygon and Scinax led to the suggestion of some mechanisms responsible for these changes, such as pericentromeric inversions associated with addition or loss of repetitive sequences. In addition, our study supports the accumulation of repetitive sequences as one of the processes of this karyotypic differentiation [12, 18].…”

“…The results showed a diploid number of 2 n = 24 and a fundamental number of NF = 48 for all species of the genera Boana, Bokermannohyla, Ololygon, and Scinax , a conservative pattern well known for these genera [11, 15, 16, 18, 19, 22, 33‒36]. In contrast, species of the genus Dendropsophus showed 2 n = 30, supporting the hypothesis that this characteristic is a synapomorphy of the genus, in contrast to the genus Xenohyla , also from the tribe Dendropsophini, which has 2 n = 24 [2, 14].…”

“…In addition to the diploid number, the NORs and 18S sequences have conserved characteristics and are found at the same loci in species within these genera or within species groups (see references in online suppl. material) [10‒19].…”

Distribuição geográfica de Scinax crospedospilus (Anura, Hylidae), incluindo novos registros na Mata Atlântica de Minas Gerais (Brasil)

“…No presente estudo realizou-se uma revisão bibliográfica e verificou-se que, após a descrição original, Scinax crospedospilus foi sendo paulatinamente registrado em diversas localidades na Mata Atlântica dos estados do Rio de Janeiro, São Paulo e Minas Gerais (Araujo et al, 2010;Araujo et al, 2013;Assis & Feio, 2017;Bang et al, 2017;Bertoluci, 1998;Bertoluci & Rodrigues, 2002;Bevier et al, 2008;Brusquetti et al, 2014;Carvalho et al 2008;Cochran, 1955;Condez et al, 2009;Conte et al, 2016;Forlani et al, 2010;Garcia et al, 2012;Garey et al, 2014;Gruber et al, 2017;Heyer et al, 1990;Lacerda et al, 2014;Leite et al, 2019;Lourenço-de-Moraes et al, 2018;Lutz, 1973;Lyra et al, 2017;Magrini et al, 2011;Moroti et al, 2019aMoroti et al, , 2019bMoura et al, 2012;Neves et al, 2017a;Neves et al, 2017b;Pacheco et al, 2016;Pereira et al, 2016;Pires & Feio, 2017;Pugliese et al, 2004;Silva et al, 2011;Silva et al, 2016;Silva et al, 2017;Silva et al, 2018;Silveira et al, 2019;Souza et al, 2016;Verdade et al, 2009). Em Minas Gerais, Lutz (1973)...…”