Parallel polymorphisms for supernumerary heterochromatin in Dichroplus elongatus (Orthoptera): - Effects on recombination and fertility
Natural populations of Dichroplus elongatus often exhibit diverse forms of supernumerary heterochromatin. In Tafi Viejo, Tucumán (Argentina), parallel polymorphisms for extra segments on pairs M6, S9 (proximal) and S10 (distal) and a mitotically unstable B chromosome were detected. The segments prod...
| Autores principales: | , , |
|---|---|
| Formato: | JOUR |
| Acceso en línea: | http://hdl.handle.net/20.500.12110/paper_00166707_v84_n3_p155_Loray |
| Aporte de: |
| id |
todo:paper_00166707_v84_n3_p155_Loray |
|---|---|
| record_format |
dspace |
| spelling |
todo:paper_00166707_v84_n3_p155_Loray2023-10-03T14:14:28Z Parallel polymorphisms for supernumerary heterochromatin in Dichroplus elongatus (Orthoptera): - Effects on recombination and fertility Loray, M.A. Remis, M.I. Vilardi, J.C. Natural populations of Dichroplus elongatus often exhibit diverse forms of supernumerary heterochromatin. In Tafi Viejo, Tucumán (Argentina), parallel polymorphisms for extra segments on pairs M6, S9 (proximal) and S10 (distal) and a mitotically unstable B chromosome were detected. The segments produce intrachromosome effects excluding chiasmata from their neigbourhood and displacing them to regions distal to the extra heterochromatin. The individuals bearing simultaneously the B and the segment on M6 show a decrease in the frequency of interstitial chismata (Xi) while those carrying only segments on M6 or S10 have an increase of this variable when compared with standard males. The between cell variance of Xi is also higher in M6 segment carriers. B individuals present an increase of abnormal spermatid frequency which may be explained by the simultaneous occurrence of two mechanisms: 1) lagging of supernumeraries and 2) physiological effects of B's affecting the meiosis even in cells lacking them. The intra and interchromosome effects may be important for the plasticity of populations allowing recombination to explore new chromosome regions. The B polymorphism seems to be stable which points to an advantage of B carriers and/or the occurrence of accumulation mechanisms counterbalancing their negative effects on fertility. © 1991 Kluwer Academic Publishers. Fil:Loray, M.A. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Remis, M.I. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Vilardi, J.C. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. JOUR info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/2.5/ar http://hdl.handle.net/20.500.12110/paper_00166707_v84_n3_p155_Loray |
| institution |
Universidad de Buenos Aires |
| institution_str |
I-28 |
| repository_str |
R-134 |
| collection |
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
| description |
Natural populations of Dichroplus elongatus often exhibit diverse forms of supernumerary heterochromatin. In Tafi Viejo, Tucumán (Argentina), parallel polymorphisms for extra segments on pairs M6, S9 (proximal) and S10 (distal) and a mitotically unstable B chromosome were detected. The segments produce intrachromosome effects excluding chiasmata from their neigbourhood and displacing them to regions distal to the extra heterochromatin. The individuals bearing simultaneously the B and the segment on M6 show a decrease in the frequency of interstitial chismata (Xi) while those carrying only segments on M6 or S10 have an increase of this variable when compared with standard males. The between cell variance of Xi is also higher in M6 segment carriers. B individuals present an increase of abnormal spermatid frequency which may be explained by the simultaneous occurrence of two mechanisms: 1) lagging of supernumeraries and 2) physiological effects of B's affecting the meiosis even in cells lacking them. The intra and interchromosome effects may be important for the plasticity of populations allowing recombination to explore new chromosome regions. The B polymorphism seems to be stable which points to an advantage of B carriers and/or the occurrence of accumulation mechanisms counterbalancing their negative effects on fertility. © 1991 Kluwer Academic Publishers. |
| format |
JOUR |
| author |
Loray, M.A. Remis, M.I. Vilardi, J.C. |
| spellingShingle |
Loray, M.A. Remis, M.I. Vilardi, J.C. Parallel polymorphisms for supernumerary heterochromatin in Dichroplus elongatus (Orthoptera): - Effects on recombination and fertility |
| author_facet |
Loray, M.A. Remis, M.I. Vilardi, J.C. |
| author_sort |
Loray, M.A. |
| title |
Parallel polymorphisms for supernumerary heterochromatin in Dichroplus elongatus (Orthoptera): - Effects on recombination and fertility |
| title_short |
Parallel polymorphisms for supernumerary heterochromatin in Dichroplus elongatus (Orthoptera): - Effects on recombination and fertility |
| title_full |
Parallel polymorphisms for supernumerary heterochromatin in Dichroplus elongatus (Orthoptera): - Effects on recombination and fertility |
| title_fullStr |
Parallel polymorphisms for supernumerary heterochromatin in Dichroplus elongatus (Orthoptera): - Effects on recombination and fertility |
| title_full_unstemmed |
Parallel polymorphisms for supernumerary heterochromatin in Dichroplus elongatus (Orthoptera): - Effects on recombination and fertility |
| title_sort |
parallel polymorphisms for supernumerary heterochromatin in dichroplus elongatus (orthoptera): - effects on recombination and fertility |
| url |
http://hdl.handle.net/20.500.12110/paper_00166707_v84_n3_p155_Loray |
| work_keys_str_mv |
AT lorayma parallelpolymorphismsforsupernumeraryheterochromatinindichropluselongatusorthopteraeffectsonrecombinationandfertility AT remismi parallelpolymorphismsforsupernumeraryheterochromatinindichropluselongatusorthopteraeffectsonrecombinationandfertility AT vilardijc parallelpolymorphismsforsupernumeraryheterochromatinindichropluselongatusorthopteraeffectsonrecombinationandfertility |
| _version_ |
1807322865396088832 |