Seppo Nokkala

Summary

Affiliation: University of Turku
Country: Finland

Publications

  1. ncbi First evidence of polyploidy in Psylloidea (Homoptera, Sternorrhyncha): a parthenogenetic population of Cacopsylla myrtilli (W. Wagner, 1947) from northeast Finland is apomictic and triploid
    Seppo Nokkala
    Laboratory of Genetics, Department of Biology, University of Turku, Turku, 20014, Finland
    Genetica 133:201-5. 2008
  2. ncbi Achiasmate segregation of a B chromosome from the X chromosome in two species of psyllids (Psylloidea, Homoptera)
    S Nokkala
    Department of Biology, University of Turku, Finland
    Genetica 108:181-9. 2000
  3. ncbi Mitotic and meiotic chromosomes in Somatochlora metallica (Cordulidae, Odonata). The absence of localized centromeres and inverted meiosis
    Seppo Nokkala
    Department of Biology, University of Turku, Finland
    Hereditas 136:7-12. 2002
  4. ncbi The origin of the achiasmatic XY sex chromosome system in Cacopsylla peregrina (Frst.) (Psylloidea, Homoptera)
    Seppo Nokkala
    Laboratory of Genetics, Department of Biology, University of Turku, FIN 20014 Turku, Finland
    Genetica 119:327-32. 2003
  5. ncbi Automictic and apomictic parthenogenesis in psocids (Insecta: Psocoptera)
    Seppo Nokkala
    Laboratory of Genetics, Department of Biology, University of Turku, FIN 20014, Turku, Finland
    Folia Biol (Krakow) 54:19-22. 2006
  6. ncbi Holocentric chromosomes in meiosis. II. The modes of orientation and segregation of a trivalent
    S Nokkala
    Laboratory of Genetics, Department of Biology, University of Turku, FIN 20014, Turku, Finland
    Chromosome Res 14:559-65. 2006
  7. ncbi Holocentric chromosomes in meiosis. I. Restriction of the number of chiasmata in bivalents
    S Nokkala
    Laboratory of Genetics, Department of Biology, University of Turku, FIN 20014 Turku, Finland
    Chromosome Res 12:733-9. 2004
  8. ncbi Dynamics of decapentaplegic expression during regeneration of the Drosophila melanogaster wing imaginal disc
    Jaakko Mattila
    Laboratory of Genetics, Department of Biology, University of Turku, Finland
    Int J Dev Biol 48:343-7. 2004
  9. ncbi Interaction of B chromosomes with A or B chromosomes in segregation in insects
    S Nokkala
    Laboratory of Genetics, Department of Biology, University of Turku, Turku, Finland
    Cytogenet Genome Res 106:394-7. 2004
  10. ncbi Cytological analysis of oogenesis
    Seppo Nokkala
    Laboratory of Genetics, Department of Biology, University of Turku, Turku, Finland
    Methods Mol Biol 247:129-37. 2004

Collaborators

Detail Information

Publications16

  1. ncbi First evidence of polyploidy in Psylloidea (Homoptera, Sternorrhyncha): a parthenogenetic population of Cacopsylla myrtilli (W. Wagner, 1947) from northeast Finland is apomictic and triploid
    Seppo Nokkala
    Laboratory of Genetics, Department of Biology, University of Turku, Turku, 20014, Finland
    Genetica 133:201-5. 2008
    ..The distribution of bisexual and parthenogenetic populations of C. myrtilli throughout the world is briefly given, and a possible origin of the triploid parthenogenetic population is discussed...
  2. ncbi Achiasmate segregation of a B chromosome from the X chromosome in two species of psyllids (Psylloidea, Homoptera)
    S Nokkala
    Department of Biology, University of Turku, Finland
    Genetica 108:181-9. 2000
    ..The regular segregation of a B chromosome from the X chromosome may obscure the distinction of a B chromosome and an achiasmate Y chromosome in some cases...
  3. ncbi Mitotic and meiotic chromosomes in Somatochlora metallica (Cordulidae, Odonata). The absence of localized centromeres and inverted meiosis
    Seppo Nokkala
    Department of Biology, University of Turku, Finland
    Hereditas 136:7-12. 2002
    ..Thus genuine dyads segregate at the first anaphase. Meiosis in these male dragonflies is thus pre-reductional or conventional, not post-reductional or inverted, as has been previously proposed...
  4. ncbi The origin of the achiasmatic XY sex chromosome system in Cacopsylla peregrina (Frst.) (Psylloidea, Homoptera)
    Seppo Nokkala
    Laboratory of Genetics, Department of Biology, University of Turku, FIN 20014 Turku, Finland
    Genetica 119:327-32. 2003
    ....
  5. ncbi Automictic and apomictic parthenogenesis in psocids (Insecta: Psocoptera)
    Seppo Nokkala
    Laboratory of Genetics, Department of Biology, University of Turku, FIN 20014, Turku, Finland
    Folia Biol (Krakow) 54:19-22. 2006
    ..Females of Ectopsocus meridionalis Ribaga and Valenzuela sp. display 3n = 27, and 27 univalent chromosomes are present in oocyte metaphase I. Thus, meiosis in these species is of the apomictic type...
  6. ncbi Holocentric chromosomes in meiosis. II. The modes of orientation and segregation of a trivalent
    S Nokkala
    Laboratory of Genetics, Department of Biology, University of Turku, FIN 20014, Turku, Finland
    Chromosome Res 14:559-65. 2006
    ..The existence of post-reductional behaviour of holocentric bivalents and multivalents is discussed...
  7. ncbi Holocentric chromosomes in meiosis. I. Restriction of the number of chiasmata in bivalents
    S Nokkala
    Laboratory of Genetics, Department of Biology, University of Turku, FIN 20014 Turku, Finland
    Chromosome Res 12:733-9. 2004
    ..The elimination of the cells carrying bivalents with more than two chiasmata creates a strong selection against the formation of more than two chiasmata in holocentric bivalents...
  8. ncbi Dynamics of decapentaplegic expression during regeneration of the Drosophila melanogaster wing imaginal disc
    Jaakko Mattila
    Laboratory of Genetics, Department of Biology, University of Turku, Finland
    Int J Dev Biol 48:343-7. 2004
    ..However, we did not find evidence of an upregulation of dpp expression during the regeneration process...
  9. ncbi Interaction of B chromosomes with A or B chromosomes in segregation in insects
    S Nokkala
    Laboratory of Genetics, Department of Biology, University of Turku, Turku, Finland
    Cytogenet Genome Res 106:394-7. 2004
    ..Apparently, these re-orientations mask any achiasmatic segregation mechanism that might operate during meiotic prophase in these insects...
  10. ncbi Cytological analysis of oogenesis
    Seppo Nokkala
    Laboratory of Genetics, Department of Biology, University of Turku, Turku, Finland
    Methods Mol Biol 247:129-37. 2004
  11. ncbi Role of Jun N-terminal Kinase (JNK) signaling in the wound healing and regeneration of a Drosophila melanogaster wing imaginal disc
    Jaakko Mattila
    Laboratory of Genetics, Department of Biology, University of Turku, Finland
    Int J Dev Biol 49:391-9. 2005
    ..A model describing the determination of blastema size is discussed...
  12. ncbi Glycoproteins with N-acetylglucosamine and mannose residues in Chinese hamster metaphase chromosomes
    J Myllyharju
    Department of Biology, University of Turku, Finland
    Hereditas 124:251-9. 1996
    ..These data suggest that chromosomal glycoproteins containing N-acetylglucosamine and mannose residues play a role in the higher order structural organization of metaphase chromosomes...
  13. ncbi Chromosome numbers of two sucking louse species (Insecta, Phthiraptera, Anoplura)
    Natalia Golub
    Department of Karyosystematics, Zoological Institute Russian Academy of Sciences, 199034 St. Petersburg
    Hereditas 141:94-6. 2004
  14. ncbi First evidence of sex chromosome pre-reduction in male meiosis in the Miridae bugs (Heteroptera)
    Snejana Grozeva
    Institute of Zoology, Bulgarian Academy of Sciences, 1 Tsar Osvoboditel, 1000 Sofia, Bulgaria
    Folia Biol (Krakow) 54:9-12. 2006
    ..This is the first evidence of sex chromosome pre-reduction in the family Miridae. Data on C-heterochromatin distribution and its composition in the chromosomes of this species are discussed...
  15. ncbi A new approach to the auchenorrhyncha (Hemiptera, Insecta) cytogenetics: chromosomes of the meadow spittlebug Philaenus spumarius (L.) examined using various chromosome banding techniques
    Valentina G Kuznetsova
    Department of Karyosystematics, Zoological Institute, Russian Academy of Sciences, 199034 St Petersburg, Russia
    Folia Biol (Krakow) 51:33-40. 2003
    ..No defined signals were observed in any chromosome treated with DAPI. After CMA3- staining, bright fluorescent signals were obtained in the NOR-bearing chromosomes, suggesting GC-rich DNA bound to the NORs...
  16. ncbi C-heterochromatin and extra (B) chromosome distribution in six species of the Nabis (Heteroptera, Nabidae) with the modal male karyotype 2n = 16 + XY
    Snejana Grozeva
    Institute of Zoology, Bulgarian Academy of Sciences, 1 Tsar Osvoboditel, 1000 Sofia, Bulgaria
    Folia Biol (Krakow) 51:13-21. 2003
    ..Only the Y usually showed relative stability ofthe C-banding pattern. In four of six species, extra (B) chromosomes were observed and their behaviour in meiosis described...