Open Access #2 2021
Abstract Hybridogenesis in an interspecific hybrid frog is a coupling mechanism in the gametogenic cell line that eliminates the genome of one parental species with endoduplication of the remaining genome of the other parental species. It has been intensively investigated in the edible frog Pelophylax kl. esculentus (RL), a natural hybrid between the marsh frog P. ridibundus (RR) and the pool frog P. lessonae (LL). However, the genetic mechanisms involved remain unclear. Here, we investigated the water frogs in the western Russian territory. In three of the four populations, we genetically identified 16 RL frogs living sympatrically with the parental LL species, or with both parental species. In addition, two populations contained genome introgression with another species, P. bedriagae (BB) (a close relative of RR). In the gonads of 13 RL frogs, the L genome was eliminated, producing gametes of R (or R combined with the B genome). In sharp contrast, one RL male eliminated the L or R genome, producing both R and L sperm. We detected a variation in genome elimination within a population. Based on the genetic backgrounds of RL frogs, we hypothesize that the introgression of the B genome resulted in the change in choosing a genome to be eliminated. © 2021 by the authors. Licensee MDPI, Basel, Switzerland. ; This research was supported by JSPS and Russian Foundation for Basic Research (RFBR) under the Japan–Russia Research Cooperative Program (2018–2019), the Russian Foundation for Basic Research (grant no. 18-54-50013 to V.V.), and the program 211 of the Government of the Russian Federation (agreement no. 02.A03.21.0006). This study was performed within the framework of the state contract with the Institute of Plant and Animal Ecology, Ural Branch of the Russian Academy of Sciences.
