A1 Refereed original research article in a scientific journal
Direction of karyotype evolution in the bug family Nabidae (Heteroptera): New evidence from 18S rDNA analysis
Authors: Nokkala C, Kuznetsova V, Grozeva S, Nokkala S
Publisher: CZECH ACAD SCI, INST ENTOMOLOGY
Publication year: 2007
Journal: European Journal of Entomology
Journal name in source: EUROPEAN JOURNAL OF ENTOMOLOGY
Journal acronym: EUR J ENTOMOL
Volume: 104
Issue: 4
First page : 661
Last page: 665
Number of pages: 5
ISSN: 1210-5759
DOI: https://doi.org/10.14411/eje.2007.083
Web address : https://www.eje.cz/artkey/eje-200704-0004_Direction_of_karyotype_evolution_in_the_bug_family_Nabidae_Heteroptera_New_evidence_from_18S_rDNA_analysis.php
Abstract
The bug family Nabidae (Heteroptera) includes taxa showing either a low chromosome number 2n = 16 + XY or high chromosome numbers 2n = 26 or 32 + XY. In order to reveal the direction of karyotype evolution in the family, a molecular phylogeny of the family was created to reveal the taxon closest to the ancestral type and hence the ancestral karyotype. The phylogeny was based on a partial sequence of the 18S rDNA gene of both high and low chromosome number species belonging to the subfamilies Prostemmatinae and Nabinae. Phylogeny created by the Neighbour Joining method separated the subfamilies, Prostemmatinae and Nabinae, which form sister groups at the base of this phylogenetic tree, as well as within the Nabinae, tribes Nabini and Arachnocorini. Combining karyosystematic data with the phylogeny of the family indicated that the ancestral karyotype was a high chromosome number, consisting of 2n = 32 + XY. During the course of evolution changes have occurred both in meiotic behaviour of the sex chromosomes and in the number of autosomes. The direction of karyotype evolution was from a high to low autosome number. Abrupt decreases in the number of autosomes have occurred twice; firstly when the tribe Arachnocorini differentiated from the main stem in the subfamily Nabinae,and secondly within the tribe Nabini, when within the genus Nabis 2n = 16 + XY species diverged from the 2n = 32 + XY species. A scheme of the sequence of events in karyotype evolution during the evolution of the Nabidae is presented.
The bug family Nabidae (Heteroptera) includes taxa showing either a low chromosome number 2n = 16 + XY or high chromosome numbers 2n = 26 or 32 + XY. In order to reveal the direction of karyotype evolution in the family, a molecular phylogeny of the family was created to reveal the taxon closest to the ancestral type and hence the ancestral karyotype. The phylogeny was based on a partial sequence of the 18S rDNA gene of both high and low chromosome number species belonging to the subfamilies Prostemmatinae and Nabinae. Phylogeny created by the Neighbour Joining method separated the subfamilies, Prostemmatinae and Nabinae, which form sister groups at the base of this phylogenetic tree, as well as within the Nabinae, tribes Nabini and Arachnocorini. Combining karyosystematic data with the phylogeny of the family indicated that the ancestral karyotype was a high chromosome number, consisting of 2n = 32 + XY. During the course of evolution changes have occurred both in meiotic behaviour of the sex chromosomes and in the number of autosomes. The direction of karyotype evolution was from a high to low autosome number. Abrupt decreases in the number of autosomes have occurred twice; firstly when the tribe Arachnocorini differentiated from the main stem in the subfamily Nabinae,and secondly within the tribe Nabini, when within the genus Nabis 2n = 16 + XY species diverged from the 2n = 32 + XY species. A scheme of the sequence of events in karyotype evolution during the evolution of the Nabidae is presented.