Federica Deidda

Karyotype, ribosomal genes, and telomeric sequences in the crayfish Procambarus clarkii (Decapoda: Cambaridae)

Mitotic and meiotic chromosomes of the crayfish Procambarus clarkii (Girard, 1852) were characterized by means of heterochromatin staining techniques (C-, DAPI- and CMA3-bandings), and FISH of major ribosomal genes and telomeric pentameric repeat (TTAGG)n. Nucleolar organizer regions have been located on four chromosome pairs. GC-rich heterochromatin was mostly associated with NORs, and brightly fluorescent centromeric/pericentromeric AT-rich bands were present in most chromosomes. Telomeric pentameric repeats (TTAGG)n, occurred in all the P. clarkii telomeres and in the interstitial region of the largest chromosome pair, not co-located to ribosomal genes; as possible explanation of the origin of this chromosome, a fusion event was hypothesized.

Comparative cytogenetics in four species of Palinuridae: B chromosomes, ribosomal genes and telomeric sequences

The evolutionary pathway of Palinuridae (Crustacea, Decapoda) is still controversial, uncertain and unexplored, expecially from a karyological point of view. Here we describe the South African spiny lobster Jasus lalandii karyotype: n and 2n values, heterochromatin distribution, nucleolar organizer region (NOR) location and telomeric repeat structure and location. To compare the genomic and chromosomal organization in Palinuridae we located NORs in Panulirus regius, Palinurus gilchristi and Palinurus mauritanicus: all species showed multiple NORs. In J. lalandii NORs were located on three chromosome pairs, with interindividual polymorphism. In P. regius and in the two Palinurus species NORs were located on two chromosome pairs. In the two last species 45S ribosomal gene loci were also found on B chromosomes. In addition, the nature and location of telomeric repeats were investigated by FISH in J. lalandii, P. gilchristi, P. mauritanicus Palinurus elephas, and P. regius (Palinuridae, Achelata), and in Scyllarus arctus (Scyllaridae, Achelata): all these Achelata species showed the (TTAGG)n pentameric repeats. Furthermore, in J. lalandii these repeats occurred in all the telomeres and in some interstitial chromosomal sites, associated with NORs.

Co-localization of ribosomal and telomeric sequences in Leptynia (Insecta: Phasmatodea)

Abstract Stick insects have been studied mainly for non-conventional reproduction modes, such as parthenogenesis, hybridogenesis and androgenesis. Parallel karyological investigations have evidenced extensive numerical and structural chromosome re-patterning, particularly evident in hybrid parthenogenetic taxa. Chromosome sets of bisexual Leptynia (Pantel) species show an evolutionary trend from 40 to 36 chromosomes and are characterized by cytological satellites of variable size and localization. We performed fluorescence in situ hybridization (FISH) analysis using 45S ribosomal genes and pentameric (TTAGG)n telomere sequences as probes in two strictly related but karyotypically distinct species, L. montana Scali (2n = 38/37; XX/XO) and L. attenuata Pantel (2n = 36). L. attenuata has recently been split into three subspecies (L. attenuata attenuata, L. attenuata iberica and L. attenuata algarvica), and found to share an XX/XY sex chromosome formula, unusual for stick insects. FISH by 45S rDNA sequences consistently labelled the short arm of the 4th chromosome pair, often of a variable size. Silver staining showed that nucleolar organizer regions (NORs) are active. FISH of the telomeric repeats, besides ordinary telomeres, also labelled the short arm of this same pair. The use of both probes in double FISH analysis fully confirmed the co-localization of ribosomal and telomeric highly repeated sequences. Since it is increasingly emerging that the co-localization of NORs and telomeric sequences appears to be a feature shared by evolutionarily distant animals, its possible role is discussed.

Comparative cytogenetics of six Indo‐Pacific moray eels (Anguilliformes: Muraenidae) by chromosomal banding and fluorescence in situ hybridization

A comparative cytogenetic analysis, using both conventional staining techniques and fluorescence in situ hybridization, of six Indo-Pacific moray eels from three different genera (Gymnothorax fimbriatus, Gymnothorax flavimarginatus, Gymnothorax javanicus, Gymnothorax undulatus, Echidna nebulosa and Gymnomuraena zebra), was carried out to investigate the chromosomal differentiation in the family Muraenidae. Four species displayed a diploid chromosome number 2n = 42, which is common among the Muraenidae. Two other species, G. javanicus and G. flavimarginatus, were characterized by different chromosome numbers (2n = 40 and 2n = 36). For most species, a large amount of constitutive heterochromatin was detected in the chromosomes, with species-specific C-banding patterns that enabled pairing of the homologous chromosomes. In all species, the major ribosomal genes were localized in the guanine-cytosine-rich region of one chromosome pair, but in different chromosomal locations. The (TTAGGG)n telomeric sequences were mapped onto chromosomal ends in all muraenid species studied. The comparison of the results derived from this study with those available in the literature confirms a substantial conservation of the diploid chromosome number in the Muraenidae and supports the hypothesis that rearrangements have occurred that have diversified their karyotypes. Furthermore, the finding of two species with different diploid chromosome numbers suggests that additional chromosomal rearrangements, such as Robertsonian fusions, have occurred in the karyotype evolution of the Muraenidae.

XX/XY sex chromosome system and chromosome markers in the snake eel Ophisurus serpens (Anguilliformes: Ophichtidae)

ABSTRACT We report evidence of an XX/XY sex chromosome system in the snake eel Ophisurus serpens (Anguilliformes: Ophichthidae). We characterized the male and female karyotypes by C-, replication- and HaeIII-bandings. The 45S and 5S ribosomal gene families were located using dual fluorescence in situ hybridization, which showed that the 5S rDNA sites were present on the X chromosome, beside an autosome pair. FISH with a telomeric peptide nucleic acid probe enabled recognition of Interstitial Telomeric Sequences (ITSs), likely remnants of chromosomal rearrangements, in five chromosome pairs, including the rDNA-bearing ones. Possible mechanisms of the origin of sex chromosomes in this species are discussed, considering the presence of a sex-linked marker and ITSs.

5S ribosomal gene family in the moray eel Gymnothorax unicolor (Anguilliformes: Muraenidae)

amazing diversity of life, including over 2,000 species of vascular plants, exotic mammals such as tapirs, giant anteaters, howler monkeys, ocelots, and jaguars, in addition to hundreds of different bird species and thousands of different insects, the choice of Foz is an excellent analogy for the diverse approaches and systems chromosome biologists explore, and that will be emphasized throughout this conference. The 2016 ICC program offers seven sessions, beginning with a session on Chromosome Structure and Nuclear Architecture, highlighting the influences and interactions chromosomes have on the three-dimensional space of the nucleus. Session II will focus on Specialized Chromosomes, such as sex chromosomes and B chromosomes, whose structure and behavior are often distinguished from that of autosomal chromosomes. Population and Evolutionary Chromosome Biology, the third session, covers a synthesis of chromosome biology and The International Chromosome Conferences (ICC) originated from the Oxford Chromosome Conferences, inaugurated by C.D. Darlington and K.R. Lewis in 1964 and held subsequently in England in 1967 and 1970. The Chromosome Conference grew to an international event with its fourth meeting, held in Jerusalem, Israel in 1972, heralding the beginning of 40 years of technological advances that have expanded our understanding of chromosome biology in model and non-traditional biological systems. Having been hosted in Europe and the United States 16 times since then, this year the ICC will be held across the equator in Foz do Iguaçu, Brazil, on July 10–13, 2016. The event will bring scientists from across the globe to a biannual meeting focused on modern advances in chromosome biology, technology and theory. The Iguaçu National Park, a UNESCO World Heritage Centre, includes the Iguaçu Falls and has been chosen as one of the ‘New Natural Seven Wonders of the World’. Home to an Published online: June 2, 2016I.O. Furo a , R. Kretschmer b , R.J. Gunski c , A.D.V. Garnero c , M.A. Ferguson-Smith d , P.C.M. O ́Brien d , E.H.C. de Oliveira e, f a Programa de Pós-Graduação em Genética e Biologia Molecular, PPGBM, Universidade Federal do Pará, Belém, b PPGBM, Universidade Federal do Rio Grande do Sul, Porto Alegre, and c Programa de Pós-Graduação em Ciências Biológicas, Universidade Federal do Pampa, São Gabriel, Brazil; d Department of Veterinary Medicine, University of Cambridge, Cambridge, UK; e Instituto de Ciências Exatas e Naturais, Universidade Federal do Pará, Belém, and f Laboratório de Cultura de Tecidos e Citogenética, SAMAM, Instituto Evandro Chagas, Ananindeua, Brazil

Chromosomal location and relationships between the two ribosomal gene families in three lobsters (Crustacea, Decapoda)

Book 22 International Colloquium on Animal Cytogenetics and Genomics 2–5 July 2016, Toulouse France Dedicated to the memory of Florence Richard Edited by: Martine Yerle-Bouissou & Alain Pinton GenPhySE, Université de Toulouse, INRA, INPT, ENVT, Castanet Tolosan, France (martine.yerle@toulouse.inra.fr) Published online: 16 August 2016 # Springer Science+Business Media Dordrecht 2016The Dinosaurs dominated the terrestrial environment for around 170 million years and are probably the most successful land vertebrate group to have existed. They survived several mass extinction events before finally all non-avian species were wiped out 66 million years ago in the Cretaceous-Paleogene extinction event. The neornithes (modern birds) are their living descendants. Despite the huge phenotypic diversity seen in birds, they, and some non-avian reptiles (e.g. some turtle species) display remarkably similar karyotypes with a characteristic pattern of macro and micro chromosomes, small genome size and few repetitive elements. This suggests that these were features present early in their evolution. The availability whole genome sequences and the recent sequencing of around 50 avian genomes, 6 of which were assembled at sufficient read depth and coverage to permit visualization at the chromosomal level, has facilitated the reconstruction of the overall genome structure (karyotype) of both Saurian (bird-reptile) and Avian ancestors. Subsequent use of bioinformatic tools permitted the retracing of the gross evolutionary changes that have occurred along the Dinosaur (and various avian) lineages. Gene ontology analysis of homologous synteny blocks (HSBs) and evolutionary breakpoint regions (EBRs) of chromosomes has allowed us to search for enrichment for genes involved in chromosome rearrangement (consistent with the formation of the signature fragmented karyotype of birds (and probably dinosaurs)). Preliminary analyses of EBRs suggest that they appear to be enriched for genes involved in body size, consistent with the overall gross reduction in body size as dinosaurs evolved into birds. Our results also suggest a period of inter-and intra-chromosomal rearrangements up until around the divergence of turtles (approximately 210 MYA) with a relatively “fixed” pattern thereafter where intra-chromosomal rearrangement plus a few identifiable fissions predominated. It is reasonable therefore to speculate that this ‘avianstyle’ genome may be one of the key factors in the success of this extraordinarily diverse animal group, allowing rapid speciation through increased propensity for random segregation and genetic recombination.

FISH localization of 5S ribosomal gene family in Atlantic and Indopacif ic morays (Anguilliformes: Muraenidae)

Chromosomal abnormalities in secondary bovine oocytes matured in vitro up to 48 hours Abstract Chromosomal abnormalities in secondary bovine oocytes matured in vitro up to 48 hours. 21st International Colloquium on Animal Cytogenetics and Gene Mapping Rubessa M., Pauciullo A., Peretti V., Iannuzzi L., Ramunno L., Di Berardino D.Edited by: L. Iannuzzi, A. Perucatti, A. Iannuzzi, A. Pauciullo, V. Genualdo, D. Incarnato, L. Keller (CNRISPAAM, Naples, Italy)Sister Chromatid exchange (SCE) test in river buffalo cells treated with Furocoumarins. / Iannuzzi A.; Perucatti A.; Genualdo V.; Pauciullo A.; Pucciarelli L.; Incarnato D.; Melis R.; Porqueddu C.; Marchetti M.; Iannuzzi L.. In: CHROMOSOME RESEARCH. ISSN 0967-3849. 22(2014), pp. 421-421. Original Citation: Sister Chromatid exchange (SCE) test in river buffalo cells treated with Furocoumarins.Comparative FISH-mapping of TNF, STAT5A and MNTR1A fecundity genes on river buffalo, cattle, sheep and goat. / Iannuzzi A.; Perucatti A.; Pauciullo A.; Genualdo V.; Incarnato D.; Pucciarelli L.; De Lorenzi L.; Parma P.; Iannuzzi L.. In: CHROMOSOME RESEARCH. ISSN 0967-3849. 22(2014), pp. 418-418. Original Citation: Comparative FISH-mapping of TNF, STAT5A and MNTR1A fecundity genes on river buffalo, cattle, sheep and goat.Multicolor FISH with 10 specific painting probes for the rapid identification of the sub-metacentric river buffalo autosomes (Bubalus bubalis, 2n=50) / Pauciullo A.; Perucatti A.; Iannuzzi A.; Incarnato D.; Genualdo V.; Pucciarelli L.; Di Berardino D.; Iannuzzi L.. In: CHROMOSOME RESEARCH. ISSN 0967-3849. 22(2014), pp. 410-410. Original Citation: Multicolor FISH with 10 specific painting probes for the rapid identification of the sub-metacentric river buffalo autosomes (Bubalus bubalis, 2n=50)

Comparative cytogenetics in crustacean decapods by telomeric and ribosomal sequences mapping

Chromosomal abnormalities in secondary bovine oocytes matured in vitro up to 48 hours Abstract Chromosomal abnormalities in secondary bovine oocytes matured in vitro up to 48 hours. 21st International Colloquium on Animal Cytogenetics and Gene Mapping Rubessa M., Pauciullo A., Peretti V., Iannuzzi L., Ramunno L., Di Berardino D.Edited by: L. Iannuzzi, A. Perucatti, A. Iannuzzi, A. Pauciullo, V. Genualdo, D. Incarnato, L. Keller (CNRISPAAM, Naples, Italy)Sister Chromatid exchange (SCE) test in river buffalo cells treated with Furocoumarins. / Iannuzzi A.; Perucatti A.; Genualdo V.; Pauciullo A.; Pucciarelli L.; Incarnato D.; Melis R.; Porqueddu C.; Marchetti M.; Iannuzzi L.. In: CHROMOSOME RESEARCH. ISSN 0967-3849. 22(2014), pp. 421-421. Original Citation: Sister Chromatid exchange (SCE) test in river buffalo cells treated with Furocoumarins.Comparative FISH-mapping of TNF, STAT5A and MNTR1A fecundity genes on river buffalo, cattle, sheep and goat. / Iannuzzi A.; Perucatti A.; Pauciullo A.; Genualdo V.; Incarnato D.; Pucciarelli L.; De Lorenzi L.; Parma P.; Iannuzzi L.. In: CHROMOSOME RESEARCH. ISSN 0967-3849. 22(2014), pp. 418-418. Original Citation: Comparative FISH-mapping of TNF, STAT5A and MNTR1A fecundity genes on river buffalo, cattle, sheep and goat.Multicolor FISH with 10 specific painting probes for the rapid identification of the sub-metacentric river buffalo autosomes (Bubalus bubalis, 2n=50) / Pauciullo A.; Perucatti A.; Iannuzzi A.; Incarnato D.; Genualdo V.; Pucciarelli L.; Di Berardino D.; Iannuzzi L.. In: CHROMOSOME RESEARCH. ISSN 0967-3849. 22(2014), pp. 410-410. Original Citation: Multicolor FISH with 10 specific painting probes for the rapid identification of the sub-metacentric river buffalo autosomes (Bubalus bubalis, 2n=50)