NISCAIR Online Periodicals Repository

Research Journals >
Indian Journal of Experimental Biology (IJEB) >
IJEB Vol.45 [2007] >
IJEB Vol.45(05) [May 2007] >

Title: GC- rich heterochromatin in silver stained nucleolar organizer regions (NORs) fluoresces with Chromomycin A3 (CMA3) staining in three species of teleostean fishes (Pisces)
Authors: Das, Jayanta Kumar
Khuda-Bukhsh, Anisur Rahman
Keywords: Ag-NOR
Chromomycin A3 banding
Chromomycin A3 banding
G-C rich region
Hemibagrus menoda
Mastacembelus armatus
Sperata seenghala
Issue Date: May-2007
Publisher: CSIR
Abstract: In a bid to ascertain the molecular architecture of the silver positive regions (NORs) in chromosomes of three species of fish, namely, Hemibagrus menoda (Hamilton), Sperata seenghala (Sykes) (Fam: Bagridae) and Mastacembelus armatus (Lacep├Ęde) (Fam: Mastacembelidae), an additional staining methodology using a fluorochrome dye (Chromomycin A3) was deployed along with the AgNO3 technique. The nucleolar organizing regions (NORs) were located terminally at the shorter arms (Tp) of one pair of submetacentric chromosomes (No.3) in H. menoda (2n=58), at the longer arms (Tq) of one pair of submetacentric chromosomes (No.5) in S. seenghala (2n=50) and at the shorter arm (Tp) of one pair of homologous submetacentric chromosomes (No.6) in M. armatus (2n=48). Staining with Chromomycin A3 produced bright fluorescing zones in GC- rich heterochromatin of Ag-positive NORs. The results indicate a more general trend of existence of an overlapping region between NOR and GC- rich fluorescing zones, the active sites of rRNA genes (rDNA) in this primitive group of vertebrates although exceptions to this situation has been reported in a couple of extant fish species earlier. More data utilizing such combined methodologies are warranted to understand the structural organization of fish chromosomes more precisely.
Page(s): 413-418
ISSN: 0975-1009 (Online); 0019-5189 (Print)
Source:IJEB Vol.45(05) [May 2007]

Files in This Item:

File Description SizeFormat
IJEB 45(5) 413-418.pdf324.44 kBAdobe PDFView/Open
 Current Page Visits: 822 
Recommend this item


Online Submission of Articles |  NISCAIR Website |  National Knowledge Resources Consortium |  Contact us |  Feedback

Disclaimer: NISCAIR assumes no responsibility for the statements and opinions advanced by contributors. The editorial staff in its work of examining papers received for publication is helped, in an honorary capacity, by many distinguished engineers and scientists.

CC License Except where otherwise noted, the Articles on this site are licensed under Creative Commons License: CC Attribution-Noncommercial-No Derivative Works 2.5 India

Copyright © 2015 The Council of Scientific and Industrial Research, New Delhi. All rights reserved.

Powered by DSpace Copyright © 2002-2007 MIT and Hewlett-Packard | Compliant to OAI-PMH V 2.0

Home Page Total Visits: 162857 since 01-Sep-2015  Last updated on 21-Jun-2016Webmaster: