Hybridogenesis in the Water Frogs from Western Russian Territory: Intrapopulation Variation in Genome Elimination

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.

Piecing the barcoding puzzle of Palearctic water frogs (Pelophylax) sheds light on amphibian biogeography and global invasions

“…However, the marsh frog copy of a few individuals corresponded to other lineages, namely kurtmuelleri in the Balkans (Herczeg et al., 2016) or cf. ridibundus G in Eastern Europe (Miura et al., 2021). Miura et al.…”

Genomics of Adaptation and Speciation

“…Answering questions about speciation, adaptation, and extinction does not require the newest and most advanced sequencing technologies, and limited sets of data can be used. The examples in this issue included studies of large structural and chromosomal variation [ 9 , 13 ] (Beklemisheva et al, 2020; Galindo et al, 2021), mtDNA and/or limited nuclear marker approaches to phylogenetics [ 24 ] (Kolchanova et al, 2021), hybridogenesis [ 10 ] (Miura et al, 2021), comparative transcriptomics [ 14 ] (Zhao and Kishino, 2020), and genome-wide studies of SNP variation using a combination of low-coverage sequencing and genotyping [ 15 , 16 ] (de La Torre et al, 2021; Mahtani-Williams et al, 2020). However, newer, more contiguous assemblies may allow for a better estimation of the genetic diversity, localization, and visualization of the distribution of genome diversity in the evolutionary context of adaptation and speciation [ 21 ] (Totikov et al, 2021).…”

“…In another example, a case of hybridogenesis was demonstrated through showing genome introgressions and elimination in edible frog Pelophylax kl. esculentus (RL), a natural hybrid between the marsh frog P. ridibundus (RR) and the pool frog P. lessonae (LL) [ 10 ] (Miura et al, 2021).…”

“…(Beklemisheva et al, 2020;Galindo et al, 2021), mtDNA and/or limited nuclear marker approaches to phylogenetics[24] (Kolchanova et al, 2021), hybridogenesis[10] (Miura et al, 2021), comparative transcriptomics[14] (Zhao and Kishino, 2020), and genome-wide studies of SNP variation using a combination of low-coverage sequencing and genotyping[15,16] (de La Torre et al, 2021; Mahtani-Williams et al, 2020).…”

Activation of DNA Transposons and Evolution of piRNA Genes Through Interspecific Hybridization in Xenopus Frogs

“… Session et al (2016) reported that the allotetraploid X. laevis origin should have had two distinct subgenomes with distinct families of transposable elements (TEs), and that the two diploid progenitor species diverged about 34 million years ago (mya) and hybridized approximately 17–18 mya. Hybridogenesis, the elimination of one of the parental genomes in the germline cells and gamete production of the other parental species is another interesting phenomenon in interspecific hybridization as observed in the edible frog Pelophylax esculentus ( Miura et al, 2021 ).…”