Abstract
The B chromosomes occur in about 15% of eukaryotes species, being primarily composed of repeated DNAs and heterochromatic. Some studies have been performed regarding the anlysis of distribution, frequency, inheritance mechanisms, structure and origin of these chromosomes. On the other hand, deeper analysis related to the diversification patters of DNA sequences present in the B chromosome and shared with the A complement have not been extensively performed. Moreover, the possible gene activity of this chromosome has not been accuracy tested. The cichlid fish have been received great scientific interest due some species have passed through an extensive adaptative radiation process. In some species of this group the presence of a B chromosome was described, as observed in Haplochromis obliquidens. Among insects, the grasshoppers, such as Rhammatocerus brasiliensis, are useful models to analysis of structure and evolution of B chromosomes, however the studies still fragmented and frequently restrict to clasical chromosome analysis, except in Eyprepocnemis plorans and Locusta migratoria. The presente project aim to analyse the genomic content, origin, evolution and possible gene activity of the B chromosomes, using as models H. obliquidens e R. Brasiliensis. In these species, besides the clasic chromosomal analysis, molecular studies related to sequences present in the B chromosmes (shared with the A complemente) will be possible through the use of molecular data and tools, such as microdissection, nucleotide sequencing and genomic analysis using bioinformatics; besides the analusis of histone proteins pos-translationl modification patterns. These analysis integrating the physical mapping and molecular data are promissing in the elucidation of a miriad of questions related to B chromosome diversification mechanisms, enabiling a deeper knowledge concerning the possible biological roles of these elements in eukaryotes. (AU)
Scientific publications
(12)
(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)
MILANI, DIOGO;
RAMOS, ERICA;
LORETO, VILMA;
ANDREA MARTI, DARDO;
CARDOSO, ADAUTO LIMA;
MARTINEZ DE MORAES, KAREN CRISTIANE;
MARTINS, CESAR;
CABRAL-DE-MELLO, DIOGO CAVALCANTI.
The satellite DNA AflaSAT-1 in the A and B chromosomes of the grasshopper Abracris flavolineata.
BMC GENETICS,
v. 18,
AUG 29 2017.
Web of Science Citations: 1.
ANJOS, A.;
RUIZ-RUANO, F. J.;
CAMACHO, J. P. M.;
LORETO, V.;
CABRERO, J.;
DE SOUZA, M. J.;
CABRAL-DE-MELLO, D. C.
U1 snDNA clusters in grasshoppers: chromosomal dynamics and genomic organization.
HEREDITY,
v. 114,
n. 2,
p. 207-219,
FEB 2015.
Web of Science Citations: 12.