4/2011
vol. 92
abstract:
REVIEW PAPER Structure and functions of lampbrush chromosomes
BioTechnologia vol. 92(4) C pp. 337-344 C 2011
Online publish date: 2014/10/28
PlumX metrics:
Lampbrush Chromosomes (LBCs) are present in the oocytes of birds, lower vertebrata and invertebrates during
the prolonged prophase of the first meiotic division. Their name stems from their similarity to bottle brushes.
Lampbrush chromosome of the early prophase is a bivalent, made up of two conjugating homologues. The axis
of each homologous chromosome is formed by sister chromatids that are differentiated into regions of transcriptionally
active and inactive chromatin. Transcription activity of LBCs is observed as a mantle of symmetrically
distributed side loops along the chromosome axis. Changes in transcriptional activity are reflected in changes in
their morphology. Transcriptional activity of LBCs is directly connected with physiological processes of the body
and shows in the morphological structure of the chromosomes. The use of cytogenetic techniques and in situ
hybridization have made it possible to identify unique and repeating sequences as well as DNA replication proteins
in LBCs. Particularly, interesting prospects are offered by the possibility of using LBCs in studies of transcriptional
activity, cytogenetic investigations of karyotype evolution and genome mapping.
keywords:
meiotic chromosome, lampbrush chromosome, transcription
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