TY  - JOUR
A1  - Lamatsch, D. K.
A1  - Trifonov, V.
A1  - Schories, S.
A1  - Epplen, J. T.
A1  - Schmid, M.
A1  - Schartl, M.
T1  - Isolation of a Cancer-Associated Microchromosome in the Sperm-Dependent Parthenogen Poecilia formosa
JF  - Cytogenetic and Genome Research
N2  - In the asexual all-female fish species Poecilia formosa, the Amazon molly, supernumerary chromosomes have frequently been found in both laboratory-reared and wild-caught individuals. While wild-caught individuals with B chromosomes are phenotypically indifferent from conspecifics, individuals carrying B chromosomes from recent introgression events in the laboratory show phenotypic changes. Former analyses showed that the expression of a pigment cell locus is associated with the presence of these B chromosomes. In addition, they contain a so far unidentified locus that confers a higher susceptibility to tumor formation in the presence of pigmentation pattern. Isolation by microdissection and hybridization to metaphase chromosomes revealed that they contain one or several sequences with similarity to a highly repetitive pericentromeric and subtelomeric sequence in A chromosomes. Isolation of one particular sequence by AFLP showed that the B chromosomes contain at least 1 copy of an A-chromosomal region which is highly conserved in the whole genus Poecilia, i.e. more than 5 million years old. We propose it to be a single copy sequence.
KW  - paternal introgression
KW  - AFLP
KW  - asexual reproduction
KW  - B chromosomes
KW  - gynogenesis
KW  - microdissection
KW  - telomeres
Y1  - 2011
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-196785
SN  - 1424-8581
SN  - 1424-859X
N1  - This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.
VL  - 135
IS  - 2
ER  - 
TY  - CHAP
A1  - Schartl, Manfred
A1  - Erbelding-Denk, C.
A1  - Hölter, S.
A1  - Nanda, I.
A1  - Schmid, M.
A1  - Schröder, J. H.
A1  - Epplen, J. T.
T1  - High mating success of low rank males in Limia perugiae (Pisces: Poeciliidae) as determined by DNA-fingerprinting
N2  - Hierarchical structures among male individuals in a population are frequently reflected in differences in aggressive and reproductive behaviour and access to the females. In general social dominance requires large investments which in turn may have to be compensated for by high reproductive success. However, this hypothesis has so far only been sufficiently tested in small mating groups due to the difficulties of determining paternity by classical methods using non-molecular markers. DNA fingerprinting overcomes these problems offering the possibility to determine genetic relationships and mating patterns within larger groups. Using this approach we have recently shown (Schartl et al., 1993) that in the poeciliid fish Limia perugiae in small mating groups the dominant male has 100% mating success, while in larger groups its contribution to the offspring unexpectedly drops to zero. The reproductive failure under such social conditions is explained by the inability of the ex-male to protect all the females simultaneously against mating attempts of his numerous subordinate competitors.
KW  - DNS
KW  - Fingerprint-Verfahren
KW  - Lebendgebärende Zahnkarpfen
Y1  - 1993
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-87132
ER  -