- SHORT COMMUNICATIONS = КРАТКИЕ СООБЩЕНИЯ =
THE FIRST RECORD OF NATURAL TRANSFER OF MITOCHONDRIAL DNA FROM PELOPHYLAXCF. BEDRIAGAE INTO P. LESSONAE (AMPHIBIA, ANURA)
Alexander Yu. Ivanov1, Alexander B. Ruchin2, Alexander I. Fayzulin3**, Igor V. Chikhlyaev3, Spartak N. Litvinchuk4,5, Alexander A. Kirillov3, Anton O. Svinin6, Oleg A. Ermakov1*
1Penza State University, Russia *e-mail: [email protected] Joint Directorate of the Mordovia State Nature Reserve and National Park «Smolny», Russia
e-mail: [email protected] 3Institute of Ecology of the Volga River Basin ofRAS, Russia **e-mail: [email protected]
4Institute of Cytology RAS, Russia e-mail: [email protected] 5Dagestan State University, Russia 6Mari State University, Russia e-mail: [email protected]
Received: 28.03.2019. Revised: 19.04.2019. Accepted: 28.04.2019.
The unidirectional natural transfer of mitochondrial (mt) DNA from Pelophylax lessonae into P. ridibundus is a common phenomenon in central Europe. Cases of mtDNA exchange between P. lessonae and other non-clonal species of the genus Pelophylax have been unknown so far. In this paper, we describe the first case of mtDNA transfer from P. cf. bedriagae into P. lessonae, which was found in National Park «Smolny», Republic of Mordovia, Russia.
Key words: European water frogs, hybridisation, hybridogenesis, interspecies introgression
Introduction
There are three species of western Palearctic water frogs of the Pelophylax esculentus complex inhabiting waterbodies in the East-European Plain (Hoffmann et al., 2015): the marsh frog, Pelophylax ridibundus (Pallas, 1771), pool frog, P lessonae (Camerano, 1882) and a taxon of hybrid origin, the edible frog, P esculentus (Linnaeus, 1758). Additionally, the Anatolian marsh frog (P cf. bedriagae) has recently been revealed in some regions of Eastern Europe (Ermakov et al., 2014; Svinin et al., 2015; Zamaletdinov et al., 2015). The processes of hybridisation and hemiclonal reproduction in water frogs can lead to widespread introgression of genes in various parts of their ranges (Spolsky & Uzzell, 1984; Plotner et al., 2008;^ Dolezalkova et al., 2016; Morozov-Leonov, 2017; Cavlovic et al., 2018). The unidirectional transfer of mitochondrial (mt) DNA from P. lessonae to P. ridibundus was previously found in Poland (Spolsky & Uzzell, 1984). Of 37 P. ridibundus specimens studied, 41% had mtDNA of the pool frog. In another study, 407 specimens of P. ridibundus from an area north of 48°N latitude
and between 8°E and 22°E longitude were analysed (Plotner et al., 2008). Among them, 34% of individuals bear mtDNA of P. lessonae. According to the authors, such introgression may have occurred via the hybridogenetic P. esculentus. It is important to note the theoretically possible reverse variant of mtDNA introgression (i.e. from the marsh frog to the pool frog), but this has not yet been found.
Material and Methods
In June and August 2018, four individuals from two water bodies in Kemlyanskoe forestry of National Park «Smolny» (Ichalki district, Republic of Mordovia, Russia) were collected.
Pond 1 is a nearly round waterbody (50 x 50 m, depth up to 2 m) which is located near the village Smolny (54.732194°N, 45.296111°E). The pond is surrounded by a scarce pine (Pinus sylves-tris L.) forest with an admixture of birch (Betula pendula Roth). The bottom of the pond is sandy and silty with a dense aquatic vegetation including floating on the surface of the water. It is used as a resting place and for grazing of cattle (Fig. 1).
Fig. 1. A - pond 1 from Kemlyanskoe forestry of National Park «Smolny» (Russia); B - the edible frog (Pelophylax esculentus) from pond 1.
Pond 2 is an oval waterbody (24 x 180 m, depth up to 3 m; 54.721111°N, 45.284500°E) with a dense aquatic vegetation on the sides. It is located near the River Alatyr and has a sandy and silty bottom. The pond is used for cattle grazing.
The toe clips of the frogs were fixed in the field in 96% ethanol and were used as tissue samples. The DNA was extracted by the standard salt-extraction method (Aljanabi & Martinez, 1997) combined with lysis by proteinase K. The PCR reaction mixture (25 pL) contained 50-100 ng of DNA, 0.5 pM of each primer, 0.2 mM dNTPs, 1.5 mM MgCl2, 2.5 pL 10 x PCR buffer (10 mM Tris-HCl, pH 8.3, 50 mM KCl), and 2 units of Taq polymerase (Thermo Scientific). The products of PCR and restriction hydrolysis were analysed by electrophoresis in 6% polyacrylamide gel (glass plate dimensions 8 x 10 cm) with further dying by ethidium bromide and UV visualisation. The molecular-weight size markers were the DNA kit of pBR322 plasmid processed with restrictase Hpall (pBR/HpaII).
Identification of species was carried out using multiplex PCR based on species-specific differences in primary structure of the intron-1 of the nuclear serum albumin gene (SAI-1) (Erma-kov et al., 2019). The nuclear SAI-1 gene was amplified using the primers Pel-SA-F1 5'-TCC ATA CAA ATG TGC TAA GTA GGT T-3' and Pel-SA-R2 5'-GAC GGT AAG GGG ACA TAA TTC A-3' (Hauswaldt et al., 2012). The PCR product of P. lessonae (genotype LL) has about 300 bp length, while P. ridibundus (RR) about 850 bp length (Fig. 2). The edible frog (which has a hybrid origin) is characterised by the presence of two bands corresponding to both parental species (RL).
850
300
Fig. 2. Electrophoregram of PCR products of SAI-1 of Pelo-phylax lessonae (lane 1), P. ridibundus (2) and P. esculentus (3). M is a marker of molecular length. Length of products (in bp) is shown on the right side of the electrophoregram.
The mtDNA ND2 gene (1038 bp) was amplified with the universal primer ND2L1 5'-AAG CTT TTG GGC CCA TAC CCC-3' (Meyer, 1993) and developed specific primer ND2H1 5'-GCA AGT CCT ACA GAA ACT GAA G-3'. The following amplification conditions were used: initial denatur-ation for 1 min at 95°C, followed by 32 cycles of 94°C for 30 s, 60°C for the ND2 and 53°C for the SAI-1 pair of primers for 30 s, 72°C for 60 s, and final extension for 5 min at 72°C.
Additionally, for an individual of the pool frog the primary sequences of both ND2 (1038 bp) and SAI-1 (262 bp) genes were studied. Sequencing was performed on an ABI 3500 automatic sequencer (Applied Biosystems), using the BigDye®Terminator
3.1 (Applied Biosystems) kit and the same primers that were used for amplification.
Results and Discussion
During the five years of our study on frogs, 135 individuals of water frogs from 15 localities in various regions of Central Russia were analysed by the use of multiplex PCR (Svinin et al., 2015; Zama-letdinov et al., 2015; Ivanov et al., 2016; Fayzulin et al., 2018). A natural introgression of mtDNA in any non-clonal species of water frogs has never been observed. We found only one record in National Park «Smolny». Of two individuals collected in pond 1, one was P. lessonae and the other was P esculentus. Surprisingly, both these individuals carried mtDNA of P. cf. bedriagae (genotypes B-LL and B-RL respectively). In pond 2, only marsh frog individuals were observed. Both individuals collected here were characterised by nuclear (n) DNA of P. ridibundus, but mtDNA of P. cf. bedriagae (B-RR). Such combination of mt and nDNA markers is common for marsh frogs from the Middle Volga River basin (Ermakov et al., 2014; Zamaletdinov et al., 2015; Fayzulin et al., 2018).
The ND2 haplotype of an individual of the pool frog collected in National Park «Smolny» was absolutely identical to such in P. cf. bedriagae (GenBank number GU812116) from Atyrau (Kazakhstan; Akin et al., 2010), as well as numerous specimens of the species from the Volga River basin (Astrakhan region, Volgograd region and Nizhny Novgorod region, Republic of Tatarstan, Republic of Mari El and Republic of Mordovia of Russia; our unpublished data). The SAI-1 sequence of the individual of P. lessonae was 100% the same as in individuals of the species (FN432384) from Germany and Penza region of Russia (Plötner et al., 2009; our unpublished data).
The observed unidirectional transfer could be explained by an introgression of mtDNA via the hybridogenetic edible frog. For example, 6% of P. esculentus individuals studied previously by us had mtDNA of P. cf. bedriagae (Ermakov et al., 2019). Gametes with the P. lessonae genome can be produced by edible frogs from R-E- and R-E-L-sys-tems (Dedukh et al., 2015, 2017; Svinin et al., 2015; Biriuk et al., 2016). The cross of an edible frog female, which produces oocytes with the P. lessonae genome (or gametes of both parental species) and bears mtDNA of P. cf. bedriagae, with a male pool or edible frog, which produces sperm with the P. lessonae genome, will result into offspring of the pool frog with mtDNA of P. cf. bedriagae.
Acknowledgments
The study was supported by grants of the Russian Foundation for Basic Research (Project 18-04-00640) and partially by the governmental project «Penza State University» (no. 6.7197.2017/BCH).
References
Akin C., Can Bilgin C., Beerli P., Westaway R., Ohst T., Lit-vinchuk S.N., Uzzell T., Bilgin M., Hotz H., Guex G-D., Plötner J. 2010. Phylogeographic patterns of genetic diversity in eastern Mediterranean water frogs were determined by geological processes and climate change in the Late Cenozoic. Journal of Biogeography 37(11): 2111-2124. DOI: 10.1111/j.1365-2699.2010.02368.x Aljanabi S.M., Martinez I. 1997. Universal and rapid salt-extraction of high genomic DNA for PCR-based techniques. Nucleic Acids Research 25(22): 4692-4693. DOI: 10.1093/nar/25.22.4692 Biriuk O.V, Shabanov D.A., Korshunov A.V, Borkin L.J., Lada G.A., Pasynkova R.A., Rosanov J.M., Litvinchuk S.N. 2016. Gamete production patterns and mating systems in water frogs of the hybridogenetic Pelophylax esculentus complex in north-eastern Ukraine. Journal of Zoological Systematics and Evolutionary Research 54(3): 215-225. DOI: 10.1111/jzs.12132 Cavlovic K., Buj I., Karaica D., Jelic D., Choleva L. 2018. Composition and age structure of the Pelophylax escu-lentus complex (Anura; Ranidae) population in inland Croatia. Salamandra 54(1): 11-20. Dedukh D., Litvinchuk S., Rosanov J., Mazepa G., Saifit-dinova A., Shabanov D., Krasikova A. 2015. Optional endoreplication and selective elimination of parental genomes during oogenesis in diploid and triploid hybrid European water frogs. PLoS ONE 10(4): e0123304. DOI: 10.1371/journal.pone.0123304 Dedukh D., Litvinchuk S., Rosanov J., Shabanov D., Kra-sikova A. 2017. Mutual maintenance of di- and triploid Pelophylax esculentus hybrids in R-E systems: results from artificial crossings experiments. BMC Evolutionary Biology 17(1): 220. DOI: 10.1186/s12862-017-1063-3 Dolezalkova M., Sember A., Marec F., Rab P., Plötner J., Choleva L. 2016. Is premeiotic genome elimination an exclusive mechanism for hemiclonal reproduction in hybrid males of the genus Pelophylax? BMC Genetics 17(1): 100. DOI: 10.1186/s12863-016-0408-z Ermakov O., Ivanov A., Titov S., Svinin A., Litvinchuk S. 2019. New multiplex PCR method for identification of East European green frog species and their hybrids. Russian Journal of Herpetology. (In Press) Ermakov O.A., Fayzulin A.I., Zaks M.M., Kaybeleva E.I., Zaripova F.F. 2014. Distribution of «western» and «eastern» forms of the marsh frog Pelophylax ridibun-dus s. l. in the Samara and Saratov regions (on data of analysis of mtDNA and nDNA). Proceedings of Samara Scientific Centre of RAS 16(5-1): 409-412. [In Russian] Fayzulin A.I., Zamaletdinov R.I., Litvinchuk S.N., Rosanov Ju.M., Borkin L.J., Ermakov O.A., Ruchin A.B., Lada G.A., Svinin A.O., Bashinsky I.V., Chikhlyaev I.V.
2018. Species composition and distributional peculiarities of green frogs (Pelophylax esculentus complex) in Protected Areas of the Middle Volga Region (Russia). Nature Conservation Research 3(Suppl.1): 1-16. DOI: 10.24189/ncr.2018.056 [In Russian] Hauswaldt J.S., Hoeer M., Ogielska M., Christiansen D.G., Dziewulska-Szwajkowska D., Czernicka E., Vences M. 2012. A simplified molecular method for distinguishing among species and ploidy levels in European water frogs (Pelophylax). Molecular Ecology Resources 12(5): 797-805. DOI: 10.1111/j.1755-0998.2012.03160.x Hoffmann A., Plötner J., Pruvost N.B., Christiansen D.G., Röth-lisberger S., Choleva L., Mikulicek P., Cogalniceanu D., Sas-Kovacs I., Shabanov D., Morozov-Leonov S., Reyer H.-U. 2015. Genetic diversity and distribution patterns of diploid and polyploid hybrid water frog populations (Pelophylax esculentus complex) across Europe. Molecular Ecology 24(17): 4371-4391. DOI: 10.1111/mec.13325 Ivanov A.Yu., Zaks M.M., Kirilenko O.A., Ermakov O.A. 2016. Molecular-genetic characteristic of the edible frog from Penza Region (Russia). In: Relevant issues of current zoology and animal ecology. Penza: Publisher of the Penza State University. P. 43. [In Russian] Meyer A. 1993. Evolution of mitochondrial DNA in fishes. In: P.W. Hochachka, T.P. Mommsen (Eds.): Molecular Biology Frontiers, Biochemistry and Molecular Biology of Fishes. Vol. 2. New York: Elsevier Science Publisher. P. 1-38. Morozov-Leonov S.Yu. 2017. Hemiclone diversity in the hybrid form Pelophylax esculentus-ridibundus (Amphibia, Ranidae) from the Tisa River drainage. Cy-
tology and Genetics 51(6): 470-477. DOI: 10.3103/ S0095452717060093 Plötner J., Uzzell T., Beerli P., Spolsky C., Ohst T., Litvinchuk S.N., Guex G.-D., Reyer H.-U., Hotz H. 2008. Widespread unidirectional transfer of mitochondrial DNA: a case in western Palaearctic water frogs. Journal of Evolutionary Biology 21(3): 668-681. DOI: 10.1111/j.1420-9101.2008.01527.x Plötner J., Köhler F., Uzzell T., Beerli P., Schreiber R., Guex G.-D., Hotz H. 2009. Evolution of serum albumin in-tron-1 is shaped by a 5' truncated non-long terminal repeat retrotransposon in western Palearctic water frogs (Neobatrachia). Molecular Phylogenetics and Evolution 53(3): 784-791. DOI: 10.1016/j.ympev.2009.07.037 Spolsky C., Uzzell T. 1984. Natural interspecies transfer of mi-tochondrial DNA in amphibians. Proceedings of the National Academy of Sciences of the United States of America 81(18): 5802-5805. DOI: 10.1073/pnas.81.18.5802 Svinin A.O., Ivanov A.Yu., Zaks M.M., Litvinchuk S.N., Borkin L.J., Rosanov J.M., Ermakov O.A. 2015. Distribution of the «eastern» and «western» forms of the marsh frog, Pelophylax ridibundus, and their participation in the origin of hemi-clonal hybrids, P. esculentus in Mari El Republic. Current Studies in Herpetology 15(3-4): 120-129. [In Russian] Zamaletdinov R.I., Pavlov A.V., Zaks M.M., Ivanov A.Y., Ermakov O.A. 2015. Molecular-genetic characteristic of Pelophylax esculentus complex from the eastern range of distribution (Volga region, Tatarstan Republic). Tomsk State University Journal of Biology 3(31): 54-66. DOI: 10.17223/19988591/31/5 [In Russian]
ПЕРВАЯ НАХОДКА ЕСТЕСТВЕННОГО ПЕРЕНОСА МИТОХОНДРИАЛЬНОЙ ДНК ОТ PELOPHYLAX CF. BEDRIAGAE К P. LESSONAE (AMPHIBIA, ANURA)
А. Ю. Иванов1, А. Б. Ручин2, А. И. Файзулин3**, И. В. Чихляев3, С. Н. Литвинчук4,5, A. A. Кириллов3, А. О. Свинин6, О. А. Ермаков1*
Пензенский государственный университет, Россия *e-mail: oaermakov@list. ru 2Объединенная дирекция Мордовского государственного заповедника имени П.Г. Смидовичаи национального парка «Смольный», Россия e-mail: [email protected] 3Инстиут экологии Волжского бассейна РАН, Россия **e-mail: [email protected] 4Институт цитологии РАН, Россия e-mail: litvinchukspartak@yandex. ru 5Дагестанский государственный университет, Россия Марийский государственный университет, Россия e-mail: [email protected]
Однонаправленный естественный перенос митохондриальной ДНК от Pelophylax lessonae к P. ridibundus - обычный феномен в Центральной Европе. Другие случаи обмена мтДНК между P lessonae и другими неклональными видами рода Pelophylax не были известны. В настоящей работе мы описываем первый случай переноса мтДНК от P. cf. bedriagae к P. lessonae, найденный в национальном парке «Смольный», Республика Мордовия, Россия.
Ключевые слова: гибридизация, гибридогенез, европейские зеленые лягушки, межвидовая интрогрессия