Universidade Estadual de Santa Cruz, Departamento de Ciências Biológicas, Ilhéus, Bahia, Brazil.
Genet Mol Biol. 2011 Apr;34(2):237-9. doi: 10.1590/s1415-47572011005000010. Epub 2011 Apr 1.
The cytogenetic analysis of Frieseomelitta dispar and F. francoi revealed the chromosome numbers 2n = 30 and n = 15 and a karyotypic formula 2K = 4M+2M(t)+4A+20A(M). The number of chromosomes observed was consistent with those reported for other Frieseomelitta species. The occurrence of the M(t) chromosome and other features of the karyotype formulae suggest a close relationship between F. dispar, F. francoi and F. varia. Nevertheless, it was possible to differentiate the karyotypes of the species by DAPI/CMA(3) staining, which revealed GC-rich regions on two chromosome pairs of F. dispar: one acrocentric and one pseudoacrocentric. In F. francoi, the same kinds of regions were observed on a pair of metacentrics and on a pair of acrocentrics. Our analysis also confirmed the chromosome number conservation in Frieseomelitta and suggests that infrequent pericentric inversion could constitute a synapomorphy for the group including F. dispar, F. francoi, and F. varia.
异色木蜂和 F. francoi 的细胞遗传学分析显示染色体数目为 2n = 30 和 n = 15，核型公式为 2K = 4M+2M(t)+4A+20A(M)。观察到的染色体数目与其他 Frieseomelitta 物种的报道一致。M(t)染色体的出现和核型公式的其他特征表明，异色木蜂、F. francoi 和 F. varia 之间存在密切关系。然而，通过 DAPI/CMA(3)染色可以区分这些物种的核型，这揭示了 F. dispar 中有两条染色体对具有 GC 丰富区：一条近端着丝粒和一条假近端着丝粒。在 F. francoi 中，同样的区域也观察到在一对着丝粒染色体和一对近端着丝粒染色体上。我们的分析还证实了 Frieseomelitta 中的染色体数保守性，并表明罕见的着丝粒倒位可能是包括 F. dispar、F. francoi 和 F. varia 在内的组的一个 synapomorphy。
