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Y Rumpler

Publications and source records attributed to Y Rumpler.

At least 91 records · Page 5Linked to original sources
PubMed1985

Chromosomal evolution in Malagasy lemurs. VIII. Chromosome banding studies of Lepilemur ruficaudatus, L leucopus, and L septentrionalis.

The karyotypes of three Lepilemuridae species, Lepilemur ruficaudatus, L leucopus, and L septentrionalis, are described and compared. An almost complete analogy of chromosome banding is exhibited. Several complex chromosomal rearrangements, especially end-to-end translocations, have occurred in the evolution of these species. The chromosomal data indicate that the species studied are well separated. In addition, their common chromosomal characters show that they constitute a clearly distinct family among the lemurs.

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PubMed1985

Soluble seminal fluid proteins from various animal species.

When soluble seminal proteins from different animal species are studied by cellulose acetate electrophoresis, important differences can be observed. These differences may be related to the type of coitus and the storage and migration of spermatozoa in the female genital tract. Seminal fluid can play a role in spermatozoal maturation by affecting the distribution of the surface charge of spermatozoal membranes.

Albumins↗
PubMed1985

Aberrations of the synaptonemal complexes in a male 46,XY,-14,+der(14)t(Y;14).

An unbalanced translocation 46,XY,-14,+der(14)t(Y;14)(q11;p11) was observed in an azoospermic male, with reduced spermatogenesis and absent spermiogenesis. At the pachytene stage of spermatocyte 1, the segments of the 2 Y chromosomes, fluorescent with quinacrine mustard, were always found close together. This proximity was also demonstrated by the study of synaptonemal complexes, which showed, in addition, an unusual hypercondensation of the proximal segment of bivalent 14, adjacent to the translocated Y chromosome. This allows us to propose that this hypercondensation might correspond to an inactivation of the translocated autosome, which could be responsible of the degeneration of the germ cells.

Adult↗
PubMed1983

Chromosomal evolution in Malagasy lemurs. VII. Phylogenic relationships between Propithecus, Avahi (Indridae), Microcebus (Cheirogaleidae), and Lemur (Lemuridae).

A chromosomal banding study was carried out on Propithecus verreauxi verreauxi, P. verreauxi deckeni, and Avahi laniger laniger. Comparison of their karyotypes with those of Microcebus murinus and Lemur fulvus led to reconstruction of the ancestral Lemuriform karyotype and a determination that the branch leading to the Indridae was isolated very early, before the separation of the Lemuridae from the Cheirogaleidae. The karyotype of Avahi remained highly ancestral, whereas that of P. verreauxi was considerably modified, chiefly by Robersonian translocations.

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PubMed1983

The karyotype of Galago crassicaudatus is ancestral for lorisiforms.

The karyotype, comprised of 62 chromosomes, of Galago crassicaudatus is described. It is compared to the karyotype of Galago senegalensis and to that of the presumed common ancestor to Lorisiforms, previously reconstructed. Most of the reconstructed chromosomes were found, unmodified, in G. crassicaudatus, strengthening the validity of the reconstruction.

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PubMed1982

Chromosomal evolution in "lemurs". VI. Chromosomal banding studies of Galago senegalensis, Galago alleni, Galago demidovii and Euoticus elegantulus.

The karyotype of four Galagidae (Galago senegalensis, G. demidovii, G. alleni and Euoticus elegantulus) are studied and compared with the aid of various banding techniques. Many common chromosome segments were found, and it was possible to reconstruct a hypothetical ancestral karyotype for the family. It was also possible to show the relation between the chromosomes of Galagidae with those of two Lorisidae. The general scheme of chromosomal evolution of the Lorisiforms can be proposed, resulting from a common populational evolution followed by an accumulation of translocations, mostly of the Robertsonian type. Several pericentric inversions have also occurred in the trunk of the Lorisidae, emerging from this common population. Then, Galagidae have evolved, each species independently, by an accumulation of translocations, mostly Robertsonian, whereas Lorisidae have accumulated pericentric inversions prior diverging.

Animals↗
PubMed1982

Spermatogenesis in several intra- and interspecific hybrids of the lemur (Lemur).

Spermatogenesis of various hybrids of the genus Lemur was studied by testicular biopsy. In hybrids between species whose classification is still much debated, the germinal cells had degenerated after the pachytene stage. This abnormality was variable in intensity depending on the parents mating: L. fulvus (2N = 60) subspecies x L. macaco sometimes resulted in fertile offspring while L. fulvus collaris x L. macaco never did. We believe that the defect in spermatogenesis is mostly caused by differences in meiotic behaviour in the germinal cells. In hybrids between two species for which there is not taxonomic doubt (L. fulvus x L. rubriventer), the gonads were completely devoid of germ cells.

Animals↗
PubMed1982

[Cytogenetic study of Macaca tonkeana].

A cytogenetic study of Macaca tonkeana shows that this species has a karyotype identical with that of Macaca fascicularis although there are sufficient morphological and ecoethological differences for the taxidermists to place these animals into two different species.

Animals↗
PubMed1980

Chromosome banding analogies between a prosimian (Microcebus murinus), a platyrrhine (Cebus capucinus), and man.

The comparative study of the karyotypes of Microcebus (Lemur, Cheirogaleid) and Cebus (Platyrrhini, Ceboid) shows important similarities between nearly all large chromosomes of these two genera. Since a relationship has been previously found between the karyotypes of Homo and Cebus, a correspondence may be found between many chromosomes of man and those of Lemurs. This study enlarges the field of comparative cytogenetics at the level of the primate order.

Animals↗
PubMed1980

Chromosomal evolution in Malagasy lemurs. V. Chromosomal banding studies of Lemur fulvus albifrons, Lemur rubriventer and its hybrids with Lemur fulvus fulvus.

The karyotype of Lemur fulvus albifrons, L. rubriventer and its hybrids with L. fulvus fulvus were compared with that of L. fulvus. fulvus. The two subspecies of L. fulvus have the same karyotype. L. rubriventer differs from L. fulvus by five Robertsonian translocations and also by increased heterochromatin in the juxtacentromeric region of the X chromosome. The karyotypes in the present study compared with those of other lemurs allowed us to propose a general scheme representing the chromosomal evolution of the genus Lemur. In this genus Robertsonian translocations represent 29 of the 33 chromosomal rearrangements which have so far been identified. We cannot affirm that sterility of the hybrids is exclusively due to the accumulation of Robertsonian translocations.

Animals↗
PubMed1979

Chromosomal evolution in Malagasy lemurs. IV. Chromosome banding studies in the genuses Phaner, Varecia, Lemur, Microcebus, and Cheirogaleus.

The karotypes of five species of Malagasy lemurs are described and compared with those of 12 previously studied species or subspecies. Based on these studies, phylogenetic relationships among nearly all the species of Cheirogaleidae and Lemuridae are proposed. The karyotype of the common ancestor is identical or very similar to that of Microcebus. Nearly 60 chromosomal changes, including five intrachromosomal rearrangements of the X chromosome, have been detected during the evolution of these two families. The possible evolutionary role of the different chromosomal rearrangements is discussed.

Animals↗
PubMed1978

Chromosomal evolution in Malagasy lemurs. III. Chromosome banding studies in the genus Hapalemur and the species Lemur catta.

The karyotypes of five Malagasy lemurs are described and compared after the successive use of various banding methods. Phylogenic relationships appear to exist between the respective ancestors of Lemur catta, Hapalemur simus, H. griseus occidentalis, H. griseus ssp, and H. griseus griseus. Their karyotypes can be derived from that of L. fulvus fulvus by chromosomal rearrangements affecting mainly chromosomes 1 and X. Intense staining of juxtacentromeric heterochromatin was detected among the different subspecies of H. griseus.

Animals↗
PubMed1977

Chromosomal evolution in Malagasy lemurs. II. Meiosis in intra- and interspecific hybrids in the genus Lemur.

The chromosome analysis of meiosis in four lemurs, Lemur fulvus fulvus, L. f. collaris, L. f. albocollaris, and L. macaco, and particular hybrid crosses is reported. In metaphase I, trivalents and chain elements were detected and identified with T-banding. The study largely confirms our previous work on mitotic karyotype comparisons in the genus Lemur. The absence of chain multivalents elements in the pachytene stages of hybrid meiosis, where a chain is detected later in diakinesis, may offer evidence on the possible existence of a two-step pairing mechanism in meiotic homolog pairing. Considerations about the role of the chromosome rearrangements in establishing a gametic barrier in speciation are developed.

Animals↗
PubMed1976

Chromosomal evolution in Malagasy lemurs. I. Chromosome banding studies in the genuses Lemur and Micrcebus.

The successive use of several banding methods permitted us to compare the karyotypes of six Malagasy lemurs: Microcebus murinus, Lemur fulvus fulvus, L. f. collaris, L. f. albocollaris, L. macaco, and L. mongoz. A correspondence can be found among all clearly identifiable chromosomes. Based on rearrangements of some of the chromosomes, the karyotype of M. murinus seems to be closest to that of the hypothetical common ancestor. The karyotype of L. f fulvus, which is nearly identical to that of M. murinus, gives rise to those of other forms by several rearrangements.

Animals↗
PubMed1975

Intraspecific chromosome variability in a lemur from the north of Madagascar: Lepilemur septentrionalis, species nova.

A cytogenetical study of 25 Lepilemur from the north of Madagascar has given evidence for six karyotypes (with four diploid numbers). Four of the karyotypes with these diploid numbers--2N = 38, 2N = 36, 2N = 34--we believe evolved from one another by centric fusion; and two karyotypes resulted from the hybridization of two of these (2N = 37 and 2N = 35). The different karyotypes distinguish themselves clearly from those of other species of Lepilemur. We have named a new species, Lepilemur septentrionalis (sp. nov.) with four subspecies: L. s. andrafiamenensis (2N = 38), L. s. ankaranensis (2N = 36), L. s. sahafarensis (2N = 36), and L. s. septentrionalis (2N = 34).

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