BACKGROUND: Evolution of sturgeons and paddlefishes (order Acipenseriformes) is inherently connected with polyploidization events which resulted in differentiation of ploidy levels and chromosome numbers of present acipenseriform species. Moreover, allopolyploidization as well as autopolyploidization seems to be an ongoing process in these fishes and individuals with abnormal ploidy levels were occasionally observed within sturgeon populations. Here, we reported occurrence of Siberian sturgeon (Acipenser baerii) male with abnormal ploidy level for this species, accessed its ploidy level and chromosome number and investigate its potential sterility or fertility in comparison with normal individuals of sterlet (A. ruthenus), Russian sturgeon (A. gueldenstaedtii) and Siberian sturgeon (A. baerii). RESULTS: Acipenser ruthenus possessed 120 chromosomes, exhibiting recent diploidy (2n), A. gueldenstaedtii and A. baerii had ~245 chromosomes representing recent tetraploidy (4n), and A. baerii male with abnormal ploidy level had ~ 368 chromosomes, indicating recent hexaploidy (6n). Genealogy assessed from the mtDNA control region did not reveal genome markers of other sturgeon species and this individual was supposed to originate from spontaneous 1.5 fold increment in number of chromosome sets with respect to the number most frequently found in nature for this species. Following hormone stimulation, the spontaneous hexaploid male produced normal sperm with ability for fertilization. Fertilization of A. baerii and A. gueldenstaedtii ova from normal 4n level females with sperm of the hexaploid male produced viable, non-malformed pentaploid (5n) progeny with a ploidy level intermediate to those of the parents. CONCLUSION: This study firstly described occurrence of hexaploid individual of A. baerii and confirmed its autopolyploid origin. In addition to that, the first detailed evidence about fertility of spontaneous hexaploid sturgeon was provided. If 1.5 fold increment in number of chromosome sets occurring in diploids, resulted triploids possess odd number of chromosome sets causing their sterility or subfertility due to interference of gametogenesis. In contrast, 1.5 fold increment in number of chromosome sets in naturally tetraploid A. baerii resulted in even number of chromosome sets and therefore in fertility of the hexaploid specimen under study.

University of South Bohemia in Ceske Budejovice Faculty of Fisheries and Protection of Waters South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses Zátiší 728 2 389 25 Vodňany Czech Republic

Zobrazit více v PubMed

McLysaght A, Hokamp K, Wolfe KH. Extensive genomic duplication during early chordate evolution. Nat Genet. 2002;31:200–204. doi: 10.1038/ng884. doi:10.1038/ng884. PubMed DOI

Panopoulou G, Poustka AJ. Timing and mechanism of ancient vertebrate genome duplications – the adventure of a hypothesis. Trends Genet. 2005;21:559–567. doi: 10.1016/j.tig.2005.08.004. doi:10.1016/.tig.2005.08.004. PubMed DOI

Ventakhesh B. Evolution and diversity of fish genomes. Curr Opin Genet Dev. 2003;13:588–592. doi: 10.1016/j.gde.2003.09.001. PubMed DOI

Hoegg S, Brinkmann H, Taylor JS, Meyer A. Phylogenetic timing of the fish-specific genome correlates with the diversification of teleost fish. J Mol Evol. 2004;59:190–203. doi: 10.1007/s00239-004-2613-z. doi:10.1007/s00239-004-2613-z. PubMed DOI

Volff JN. Genome evolution and biodiversity in teleost fish. Heredity. 2005;94:280–294. doi: 10.1038/sj.hdy.6800635. doi:10.1038/sj.hdy.6800635. PubMed DOI

Froschauer A, Braasch I, Volff JN. Fish genomes; comparative genomics and vertebrate evolution. Curr Genomics. 2006;7:43–57. doi: 10.2174/138920206776389766. DOI: 1389-2029/06550.00+.00. DOI

Nelson JS. Fishes of the World. 4. New York, NY, USA: John Wiley and Sons Inc.; 2006.

Ludwig A, Belfiore NM, Pitra C, Svirsky V, Jenneckens I. Genome duplication events and functional reduction of ploidy levels in sturgeon (Acipenser; Huso and Scaphirhynchus) Genetics. 2001;158:1203–1215. PubMed PMC

Fontana F, Zane L, Pepe A, Congiu L. In: Fish cytogenetic. Pisano E, Ozof-Costaz C, Foresti F, Kapoor BG, editor. New Hampshire, NH, USA: Science Publisher Inc; 2007. Polyploidy in Acipenseriformes: cytogenetic and molecular approaches; pp. 385–403.

Vasiľev VP. In: Biology, Conservation and Sustainable Development of Sturgeons. Carmona R, Domezain A, García-Gallego M, Hernando JA, Rodríguez F, Ruiz-Rejón M, editor. The Netherlands: Springer Science; 2009. Mechanisms of polyploid evolution in fish: Polyploidy in Sturgeons; pp. 97–117. DOI: 10.1007/978-1-4020-8437-9_6.

Fontana F, Tagliavini J, Congiu C. Sturgeon genetics and cytogenetics: recent advancement and perspectives. Genetic. 2001;111:359–373. doi:10.1023/A:1013711919443. PubMed

Birstein VJ, Poletaev AI, Goncharov BF. DNA content in Eurasian sturgeon species determined by flow cytometry. Cytometry. 1993;14:377–383. doi: 10.1002/cyto.990140406. PubMed DOI

Birstein VJ, Hanner R, Desalle R. Phylogeny of the Acipenseriformes: Cytogenetic and molecular approaches. Env Biol Fishes. 1997;48:127–156. doi: 10.1023/A:1007366100353. DOI

Ludwig A, Debus L, Jenneckens I. A molecular approach for trading control of black caviar. Int Rev Hydrobiology. 2002;87:661–674. doi: 10.1002/1522-2632(200211)87:5/6<661::AID-IROH661>3.0.CO;2-S. DOI: 10.1002/1522 2632(200211)87:5/6B661::AID-IROH661C3.0.CO;2-S. DOI

Ludwig A, Lippold S, Debus L, Reinartz R. First evidence of hybridization between endangered starlets (Acipenser ruthenus) and exotic Siberian sturgeons (Acipenser baerii) in the Danube River. Biol Invasions. 2009;11:753–760. doi: 10.1007/s10530-008-9289-z. doi:10.1007/s10530-008-9289-z. DOI

Nikolyukin NI. Some observations on the histological structure of the gonads of sturgeon hybrids. Trudy VNIRO. 1964;55:145–157. (in Russian)

Flajšhans M, Vajcová V. Odd ploidy levels in sturgeon suggest a backcross of interspecific hexaploid sturgeon hybrids to evolutionary tetraploid and/or octaploid parental species. Folia Zool. 2000;49:133–138.

Arefjev VA. Sturgeon hybrids: natural reality and practical prospects. Aquac Mag. 1997;23:52–58.

Birstein VJ. In: Endangered Animals: A Reference Guide to Conflicting Issues. Reading RP, Miller B, editor. Westport, CT, USA: Greenwood Press; 2000. Sturgeons and Paddlefishes (Acipenseriformes) pp. 269–278.

Piferrer F, Beaumont A, Falguiere JC, Flajšhans M, Haffray P, Colombo L. Polyploid fish and shellfish: Production; biology and applications to aquaculture for performance improvement and genetic containment. Aquaculture. 2009;239:125–156. doi:10.1016/j.aquaculture.2009.04.036.

Gorshkova G, Gorshkov S, Gordin H, Knibb W. Karyological studies in hybrids of Beluga Huso huso (L.) and the Russian sturgeon Acipenser gueldenstaedtii Brandt. The Israeli J of Aquaculture. 1996;48:35–39.

Bytyutskyy D, Srp J, Flajšhans M. Use of Feulgen image analysis densitometry to study the effect of genome size on nuclear size in polyploid sturgeons. J Appl Ichthyol. 2012;28:704–708. doi: 10.1111/j.1439-0426.2012.02021.x. DOI

Ráb P, Arefjev VA, Rábová M. C-banded karyotype of the sterlet; Acipenser ruthenus; from the Danube River. Sturg Quart. 1996;4(Suppl 4):10–12.

Fontana F, Lanfredi M, Chicca M, Congiu L, Tagliavini J, Rossi R. Fluorescent in situ hybridization with rDNA probes on chromosomes of Acipenser ruthenus and Acipenser naccarii (Osteichthyes Acipenseriformes) Genome. 1999;42:1008–1012. doi:10.1139/g99-030.

Arefjev VA, Nikolaev AI. Cytological analysis of the reciprocal hybrids between low- and high-chromosome acipenserids; the great sturgeon; Huso huso (L.); and the Russian sturgeon; Acipenser gueldenstaedti Brandt. Cytologia. 1991;56:495–502. doi: 10.1508/cytologia.56.495. DOI

Wang W, Dong Y, Tian ZH, Chen XX, Hu HX. Heteroplasmy in mtDNA control region and phylogenetics of five sturgeons. Zool Res. 2009;30(Suppl 5):487–496.

Dudu A, Suciu R, Paraschiv M, Georgescu SE, Costache M, Berrebi P. Nuclear markers of Danube sturgeon hybridization. Int J Mol Sci. 2011;12:6796–6809. doi: 10.3390/ijms12106796. doi:ijms12106796/ijms12106796. PubMed DOI PMC

Cherfas NB, Gomelsky B, Ben–Dom N, Hulata G. Evidence for the heritable nature of spontaneous diploidization in common carp Cyprinus carpio L. eggs. Aquac Res. 1995;26:289–292. doi: 10.1111/j.1365-2109.1995.tb00914.x. doi:10.1111/j.1365-2109.1995.tb00914.x. DOI

Aegerter S, Jalabert B. Effects of post-ovulatory oocyte ageing and temperature on egg quality and on the occurrence of triploid fry in rainbow trout; Oncorhynchus mykiss. Aquaculture. 2004;231:59–71. doi: 10.1016/j.aquaculture.2003.08.019. DOI

Ezaz MT, McAndrew BJ, Penman DJ. Spontaneous diploidization of the maternal chromosome set in Nile tilapia (Oreochromis niloticus L.) eggs. Aquac Res. 2004;35:271–277. doi: 10.1111/j.1365-2109.2004.01010.x. DOI

Centofante L, Bertollo LAC, Moreira-Filho O. Comparative cytogenetics among sympatric species of Characidium (Pisces; Characiformes) Diversity analysis with the description of a ZW sex chromosome system and natural triploidy. Caryologia. 2001;54(Suppl 3):253–260.

Borin LA, Martins-Santos IC, Oliveira C. A natural triploid in Trichomycterus davisi (Siluriformes; Trichomycteridae): mitotic and meiotic characterization by chromosome banding and synaptonemal complex analyses. Genetica. 2002;115:253–258. doi: 10.1023/A:1020667526552. PubMed DOI

Fontana F, Congiu L, Mudrak VA, Quattro JM, Smith TI, Ware K, Doroshov SI. Evidence of hexaploid karyotype in shortnose sturgeon. Genome. 2008;51:113–119. doi: 10.1139/G07-112. doi:10.1139/G07-112. PubMed DOI

Zhou H, Fujimoto T, Adachi S, Yamaha E, Arai K. Genome size variation estimated by flow cytometry in Acipenser mikadoi, Huso dauricus in relation to other species of Acipenseriformes. J Appl Ichtyol. 2011;27:484–491. doi: 10.1111/j.1439-0426.2010.01648.x. doi:10.1111/j.1439-0426.2010.01648.x. DOI

Zhou H, Fujimoto T, Adachi S, Abe S, Yamaha E, Arai K. Molecular cytogenetic study on the ploidy status in Acipenser mikadoi. J Appl Ichtyol. 2013;29:51–55. doi: 10.1111/jai.12109. doi:10.1111/jai.12109. DOI

Omoto N, Maebayashi M, Adachi S, Arai K, Yamauchi K. The influence of oocyte maturational stage on hatching and triploidy rates in hybrid (bester) sturgeon Huso huso x Acipenser ruthenus. Aquaculture. 2005;245:287–294. doi: 10.1016/j.aquaculture.2004.11.008. DOI: 10.1016/j.aquaculture.2004.11.008. DOI

Drauch Schreier A, Gille D, Mahardja B, May B. Neutral markers confirm the octaploid origin reveal spontaneous autopolyploidy in white sturgeon, Acipenser transmontanus. J Appl Ichthyol. 2011;27(Suppl 2):24–33. DOI: 10.1111/j.1439-0426.2011.01873.x.

Dettlaff TA, Ginzburg AS, Schmalhausen OI. Sturgeon fishes: developmental biology and aquaculture. Springer – Verlang: Berlin, Germany; 1993.

Hochleitner M. Störe. Österreichischer Agrarverlag: Klosterneuburg, Austria; 1996. (in German)

Dzyuba B, Boryshpolets S, Shaliutina A, Rodina M, Yamaner G, Gela D, Dzyuba V, Linhart O. Spermatozoa motility; cryoresistance; and fertilizing ability in sterlet Acipenser ruthenus during sequential stripping. Aquaculture. 2012;356–357:272–278. doi:10.1016/j.aquaculture.2012.05.006.

Piros B, Glogowski J, Kolman R, Rzemieniecki A, Domagala J, Horváth Á, Urbanyi B, Ciereszko A. Biochemical characterization of Siberian sturgeon Acipenser baerii and sterlet, Acipenser ruthenus, milt plasma and spermatozoa. Fish Physiol Biochem. 2002;26:289–295. doi: 10.1023/A:1026280218957. DOI

Pšenička M, Kašpar V, Rodina M, Gela D, Hulák M, Flajšhans M. Comparative study on ultrastructure and motility parameters of spermatozoa of tetraploid and hexaploid Siberian sturgeon Acipenser baerii. J Appl Ichtyol. 2011;27:683–686. doi: 10.1111/j.1439-0426.2011.01685.x. doi:10.1111/j.1439-0426.2011.01685.x. DOI

Kolářová J, Velíšek J, Nepejchalová L, Svobodová Z, Kouřil J, Hamáčková J, Máchová J, Piačková V, Hajšlová J, Holadová K, Kocourek V, Klimánková E, Modrá H, Dobšíková R, Groch L, Novotný L. Anestethics for fish - Methodology. Vodňany, Czech Republic: University of South Bohemia in České Budějovice; Research Institute for Fisheries and Hydrobiology; 2007. in Czech.

Gela D, Rodina M, Linhart O. Controlled reproduction of sturgeons (Acipenser) - Methodology. Vodňany, Czech Republic: University of South Bohemia in České Budějovice; Research Institute for Fisheries and Hydrobiology; 2008. in Czech.

Štěch L, Linhart O, Shelton WL, Mims SD. Minimally invasive surgical removal of ovulated eggs of paddlefish (Polyodon spathula) Aqua Int. 1999;7:129–133. doi: 10.1023/A:1009253806766. DOI

Linhart O, Rodina M, Cosson J. Cryopreservation of sperm in common carp Cyprinus carpio: sperm motility and hatching success of embryos. Cryobiology. 2000;41:241–250. doi: 10.1006/cryo.2000.2284. doi:10.1006/cryo.2000.2284. PubMed DOI

Flajšhans M, Cosson J, Rodina M, Linhart O. The application of image cytometry to viability assessment in dual fluorescence-stained fish spermatozoa. Int J Cell Biol. 2004;28:955–959. doi:10.1016/j.cellbi.2004.07.014. PubMed

Linhart O, Rodina M, Flajšhans M, Mavrodiev N, Nebesarova J, Gela D, Kocour M. Studies on sperm of diploid and triploid tench (Tinca tinca L.) Aquac Int. 2006;14:9–25. doi: 10.1007/s10499-005-9010-5. DOI

Pravda D, Svobodová Z. In: Veterinary Haematology. Doubek J, Bouda J, Doubek M, Fürll M, Knotková Z, Pejřilová S, editor. Brno, Czech Republic: Noviko; 2003. Haematology of fishes; pp. 381–397. in Czech.

Lecommandeur D, Haffray P, Philippe L. Rapid flow cytometry method for ploidy determination in salmonid eggs. Aquacult Fish Managem. 1994;25:345–350.

Flajšhans M. A model approach to distinguish diploid and triploid fish by means of computer-assisted image analysis. Acta Vet Brno. 1997;66:101–110. doi: 10.2754/avb199766020101. doi:avb199766020101/avb199766020101. DOI

Fujiwara A, Nishida-Umehara C, Sakamoto T, Okamoto N, Nakayama I, Abe S. Improved fish lymphocyte culture for chromosome preparation. Genetica. 2001;111:77–89. doi: 10.1023/A:1013788626712. PubMed DOI

Völker M, Kulmann H. Sequential chromosome banding from single acetic acid fixed embryos of Chromaphyosemion killifishes (Cyprinodontiforme; Nothobranchiidae) Cybium. 2006;30(Suppl 2):171–176.

Mugue NS, Barmintseva AE, Rastorguev SM, Mugue VN, Barminstev VA. Polymorphism of the mitochondrial DNA control region in eight sturgeon species and development of a system for DNA-based species identification. Russ J Genet. 2008;44:793–798. doi: 10.1134/S1022795408070065. DOI: 10.1134/S1022795408070065. PubMed DOI

Drummond AJ, Ashton B, Buxton S, Cheung M, Cooper A, Duran C, Field M, Heled J, Kearse M, Markowitz S, Moir R, Stones-Havas S, Sturrock S, Thierer T, Wilson A. Geneious v 5.4. 2011. Available: http://www.geneious.com. PubMed

May B, Krueger CC, Kincaid HL. Genetic variation at microsatellite loci in sturgeon: primer sequence homology in Acipenser and Scaphirhynchus. Can J Fish Aquat Sci. 1997;54:1542–1547. doi: 10.1139/f97-061. doi:10.1139/cjfas-54-7-1542. DOI

McQuown EC, Sloze BL, Sheehan RJ, Rodzen J, Tranah GJ, May B. Microsatellite analysis of genetic variation in sturgeon (Acipenseridae): new primer sequences for Scaphirhynchus and Acipenser. Trans Am Fish Soc. 2000;129:1380–1388. doi: 10.1577/1548-8659(2000)129<1380:MAOGVI>2.0.CO;2. DOI 10.1577/1548-8659(2000)129<1380:MAOGVI>2.0.CO;2. DOI

King TL, Lubinski BA, Spidle AP. Microsatellite DNA variation in Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus) and cross-species amplification in the Acipenseridae. Conserv Genet. 2001;2:103–119. doi: 10.1023/A:1011895429669. doi:10.1023/A:1011895429669. DOI

Artificial whole genome duplication in paleopolyploid sturgeons yields highest documented chromosome number in vertebrates

Ploidy Levels and Fitness-Related Traits in Purebreds and Hybrids Originating from Sterlet (Acipenser ruthenus) and Unusual Ploidy Levels of Siberian Sturgeon (A. baerii)

A newly developed cloning technique in sturgeons; an important step towards recovering endangered species

Elimination of primordial germ cells in sturgeon embryos by ultraviolet irradiation

Molecular cytogenetic differentiation of paralogs of Hox paralogs in duplicated and re-diploidized genome of the North American paddlefish (Polyodon spathula)

The second highest chromosome count among vertebrates is observed in cultured sturgeon and is associated with genome plasticity