Soares Rodrigo Xavier, da Motta-Neto Clóvis Coutinho, da Costa Gideão Wagner Werneck Félix, Cioffi Marcelo de Bello, Bertollo Luiz Antônio Carlos, Borges Amanda Torres, Molina Wagner Franco
Departament of Cell Biology and Genetics, Biosciences Center, Universidade Federal do Rio Grande do Norte, Natal, RN, 59078970, Brazil.
Fish Cytogenetics Laboratory, Departament of Genetics and Evolution, Universidade Federal de São Carlos, São Carlos, SP, C.P. 676, Brazils.
Comp Cytogenet. 2021 Dec 1;15(4):429-445. doi: 10.3897/CompCytogen.v15.i4.69638. eCollection 2021.
Carangidae are an important and widespreaded family of pelagic predatory fishes that inhabit reef regions or open ocean areas, some species occupying a vast circumglobal distribution. Cytogenetic comparisons among representatives of its different tribes help to understand the process of karyotype divergence in marine ecosystems due to the variable migratory ability of species. In this sense, conventional cytogenetic investigations (Giemsa staining, Ag-NORs, and C-banding), GC base-specific fluorochrome staining and FISH mapping of ribosomal DNAs were performed. Four species, (Quoy et Gaimard, 1825) and (Valenciennes, 1883) (Naucratini), with circumtropical distributions, (Forsskål, 1775) (Carangini), widely distributed in the tropical and subtropical waters of the Indian and Pacific oceans, and (Linnaeus, 1766) (Trachinotini), distributed along the western Atlantic Ocean, were analyzed, thus encompassing representatives of three out its four tribes. All species have diploid chromosome number 2n = 48, with karyotypes composed mainly by acrocentric chromosomes (NF = 50-56). The 18S rDNA/Ag-NORs/GC+ and 5S rDNA loci were located on chromosomes likely homeologs. Karyotypes showed a pattern considered basal for the family or with small variations in their structures, apparently due to pericentric inversions. The migratory capacity of large pelagic swimmers, in large distribution areas, likely restricts the fixation of chromosome changes in Carangidae responsible for a low level of karyotype diversification.
鲹科是一个重要且分布广泛的中上层掠食性鱼类家族，栖息于珊瑚礁区域或开阔海域，一些物种具有广泛的全球分布。对其不同部落代表进行细胞遗传学比较，有助于了解由于物种迁徙能力不同，海洋生态系统中核型分化的过程。从这个意义上说，我们进行了传统的细胞遗传学研究（吉姆萨染色、银染核仁组织区和CC带带型分析）、GC碱基特异性荧光染色以及核糖体DNA的荧光原位杂交图谱分析。分析了四个物种，分布于热带地区的（Quoy et Gaimard，1825年）和（Valenciennes，1883年）（瑙克拉鲹族），广泛分布于印度洋和太平洋热带及亚热带水域的（Forsskål，1775年）（鲹族），以及分布于西大西洋的（Linnaeus，1766年）（竹筴鲹族），从而涵盖了四个部落中的三个部落的代表。所有物种的二倍体染色体数均为2n = 48，核型主要由近端着丝粒染色体组成（NF = 50 - 56）。18S rDNA/银染核仁组织区/GC +和5S rDNA位点位于可能是同源染色体的染色体上。核型显示出一种被认为是该家族基础的模式，或者其结构有小的变化，显然是由于臂间倒位。大型中上层洄游鱼类在广阔分布区域的洄游能力，可能限制了鲹科中导致核型多样化水平较低的染色体变化的固定。
