Restriction endonuclease banding and photooxidation studies of delayed QM-fluorescence of the C-heterochromatin of the small Japanese field mouse, Apodemus argenteus.

Accession number;02A0931249
Title;Restriction endonuclease banding and photooxidation studies of delayed QM-fluorescence of the C-heterochromatin of the small Japanese field mouse, Apodemus argenteus.
Author; NOMURA T (Hirosaki Univ., Aomori, Jpn) SAIGUSA K (Hirosaki Univ., Aomori, Jpn) FUKUSHI D (Hirosaki Univ., Aomori, Jpn) OBARA Y (Hirosaki Univ., Aomori, Jpn) KURO-O M (Hirosaki Univ., Aomori, Jpn)
Journal Title;Chromosome Sci
Journal Code:S0638B
ISSN:1344-1051
VOL.5;NO.3;PAGE.123-131(2001)
Figure&Table&Reference;FIG.7, TBL.3, REF.22
Pub. Country;Japan
Language;English
Abstract;We analyzed the effects of treatments with eight restriction endonucleases(REs) and of photooxidation using methylene blue, Giemsa and fluorochromes on the large C-heterochromatic region(C-block) of the X chromosome of the small Japanese field mouse(Apodemus argenteus). Both Alu I-treated and Rsa I-treated metaphase chromosomes exhibited C-band-like profiles after Giemsa staining, whereas treatment with Hae III, Dra I, Hin dIII, Hpa I or Ssp I resulted in G-band-like profiles. Treatment with Eco RI yielded a rather uniform staining profile. In control samples without RE digestion, delayed fluorescence was observed in the C-block after staining with quinacrine mustard(QM), but not after staining with chromomycin A3 or Hoechst 33258. Treatment with Alu I or Rsa I induced the dramatic conversion of fluorescence from prominent and bright to dull in the QM-stained C-block. However, after treatment with Alu I and staining with Hoechst 33258, the C-block also emitted bright fluorescence immediately after exposure to blue light at 435nm. A similar change in QM-fluorescence was also observed in the case of photooxidized C-blocks. However, no such change in QM-fluorescence was observed after treatments with each of the remaining six REs. These findings suggest that Alu I and Rsa I might influence some factor(s) that is responsible for release from delayed QM-fluorescence or that allows immediate excitation of QM molecules that have bound to the genomic DNA in the C-block of A. argenteus. (author abst.)