Previous Article | Next Article ![]()
Molecular and Cellular Biology, July 1999, p. 5096-5105, Vol. 19, No. 7
Columbia University, New York, New York
100321; Harvard Medical School, Boston,
Massachusetts 021152; University of
Kaiserslautern, D-67653 Kaiserslautern,
Germany3; and Albert Einstein
College of Medicine, Bronx, New York 104614
Received 10 February 1999/Returned for modification 1 April
1999/Accepted 13 April 1999
A-T (ataxia telangiectasia) individuals frequently display gonadal
atrophy, and Atm
0270-7306/99/$04.00+0
Copyright © 1999, American Society for Microbiology. All rights reserved.
Atm Inactivation Results in Aberrant
Telomere Clustering during Meiotic Prophase
/
mice show spermatogenic
failure due to arrest at prophase of meiosis I. Chromosomal movements
take place during meiotic prophase, with telomeres congregating on the
nuclear envelope to transiently form a cluster during the
leptotene/zygotene transition (bouquet arrangement). Since the ATM
protein has been implicated in telomere metabolism of somatic cells, we
have set out to investigate the effects of Atm inactivation
on meiotic telomere behavior. Fluorescent in situ hybridization and
synaptonemal complex (SC) immunostaining of structurally preserved
spermatocytes I revealed that telomere clustering occurs aberrantly in
Atm
/
mice. Numerous spermatocytes of
Atm
/
mice displayed locally accumulated
telomeres with stretches of SC near the clustered chromosome ends. This
contrasted with spermatogenesis of normal mice, where only a few
leptotene/zygotene spermatocytes I with clustered telomeres were
detected. Pachytene nuclei, which were much more abundant in normal
mice, displayed telomeres scattered over the nuclear periphery. It
appears that the timing and occurrence of chromosome polarization is
altered in Atm
/
mice. When we examined
telomere-nuclear matrix interactions in spermatocytes I, a significant
difference was observed in the ratio of soluble versus
matrix-associated telomeric DNA sequences between meiocytes of
Atm
/
and control mice. We propose that the
severe disruption of spermatogenesis during early prophase I in the
absence of functional Atm may be partly due to altered
interactions of telomeres with the nuclear matrix and distorted meiotic
telomere clustering.
*
Corresponding author. Mailing address: Center for
Radiological Research, College of Physicians and Surgeons, Columbia
University, VC11-213, 630 West 168th St., New York, NY 10032. Phone:
(212) 305-3911. Fax: (212) 305-3229. E-mail:
tkp1{at}columbia.edu.
This article has been cited by other articles:
| J. Bacteriol. | J. Virol. | Eukaryot. Cell |
|---|
| Microbiol. Mol. Biol. Rev. | Clin. Vaccine Immunol. | All ASM Journals |
|---|