|
|
|
|||
| Home Help Feedback Subscriptions Archive Search Table of Contents | ||||
Development, Vol 124, Issue 24 5033-5048, Copyright © 1997 by Company of Biologists
JOURNAL ARTICLES |
JH Hager and TW Cline
Department of Molecular and Cell Biology, University of California, Berkeley 94720-3204, USA.
With a focus on Sex-lethal (Sxl), the master regulator of Drosophila somatic sex determination, we compare the sex determination mechanism that operates in the germline with that in the soma. In both cell types, Sxl is functional in females (2X2A) and nonfunctional in males (1X2A). Somatic cell sex is determined initially by a dose effect of X:A numerator genes on Sxl transcription. Once initiated, the active state of SXL is maintained by a positive autoregulatory feedback loop in which Sxl protein insures its continued synthesis by binding to Sxl pre-mRNA and thereby imposing the productive (female) splicing mode. The gene splicing-necessary factor (snf), which encodes a component of U1 and U2 snRNPs, participates in this RNA splicing control. Here we show that an increase in the dose of snf+ can trigger the female Sxl RNA splicing mode in male germ cells and can feminize triploid intersex (2X3A) germ cells. These snf+ dose effects are as dramatic as those of X:A numerator genes on Sxl in the soma and qualify snf as a numerator element of the X:A signal for Sxl in the germline. We also show that female-specific regulation of Sxl in the germline involves a positive autoregulatory feedback loop on RNA splicing, as it does in the soma. Neither a phenotypically female gonadal soma nor a female dose of X chromosomes in the germline is essential for the operation of this feedback loop, although a female X-chromosome dose in the germline may facilitate it. Engagement of the Sxl splicing feedback loop in somatic cells invariably imposes female development. In contrast, engagement of the Sxl feedback loop in male germ cells does not invariably disrupt spermatogenesis; nevertheless, it is premature to conclude that Sxl is not a switch gene in germ cells for at least some sex-specific aspects of their differentiation. Ironically, the testis may be an excellent organ in which to study the interactions among regulatory genes such as Sxl, snf, ovo and otu which control female-specific processes in the ovary.
This article has been cited by other articles:
![]() |
A. L. Casper and M. Van Doren The establishment of sexual identity in the Drosophila germline Development, November 15, 2009; 136(22): 3821 - 3830. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Chau, L. S. Kulnane, and H. K. Salz Sex-lethal Facilitates the Transition From Germline Stem Cell to Committed Daughter Cell in the Drosophila Ovary Genetics, May 1, 2009; 182(1): 121 - 132. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. G. Siera and T. W. Cline Sexual Back Talk With Evolutionary Implications: Stimulation of the Drosophila Sex-Determination Gene Sex-lethal by Its Target transformer Genetics, December 1, 2008; 180(4): 1963 - 1981. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. K. M. Penn, P. Graham, G. Deshpande, G. Calhoun, A. S. Chaouki, H. K. Salz, and P. Schedl Functioning of the Drosophila Wilms'-Tumor-1-Associated Protein Homolog, Fl(2)d, in Sex-Lethal-Dependent Alternative Splicing Genetics, February 1, 2008; 178(2): 737 - 748. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Casper and M. Van Doren The control of sexual identity in the Drosophila germline Development, August 1, 2006; 133(15): 2783 - 2791. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. O. F. Penalva and L. Sanchez RNA Binding Protein Sex-Lethal (Sxl) and Control of Drosophila Sex Determination and Dosage Compensation Microbiol. Mol. Biol. Rev., September 1, 2003; 67(3): 343 - 359. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. A. Nagengast, S. M. Stitzinger, C.-H. Tseng, S. M. Mount, and H. K. Salz Sex-lethal splicing autoregulation in vivo: interactions between SEX-LETHAL, the U1 snRNP and U2AF underlie male exon skipping Development, February 1, 2003; 130(3): 463 - 471. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Andrews and B. Oliver Sex Determination Signals Control ovo-B Transcription in Drosophila melanogaster Germ Cells Genetics, February 1, 2002; 160(2): 537 - 545. [Abstract] [Full Text] [PDF] |
||||
![]() |
J Lu and B Oliver Drosophila OVO regulates ovarian tumor transcription by binding unusually near the transcription start site Development, January 5, 2001; 128(9): 1671 - 1686. [Abstract] [PDF] |
||||
![]() |
J. A. Waterbury, J. I. Horabin, D. Bopp, and P. Schedl Sex Determination in the Drosophila Germline Is Dictated by the Sexual Identity of the Surrounding Soma Genetics, August 1, 2000; 155(4): 1741 - 1756. [Abstract] [Full Text] |
||||
![]() |
L. O. F. Penalva, M. F. Ruiz, A. Ortega, B. Granadino, L. Vicente, C. Segarra, J. Valcárcel, and L. Sánchez The Drosophila fl(2)d Gene, Required for Female-Specific Splicing of Sxl and tra Pre-mRNAs, Encodes a Novel Nuclear Protein With a HQ-Rich Domain Genetics, May 1, 2000; 155(1): 129 - 139. [Abstract] [Full Text] |
||||
![]() |
C Schutt and R Nothiger Structure, function and evolution of sex-determining systems in Dipteran insects Development, January 2, 2000; 127(4): 667 - 677. [Abstract] [PDF] |
||||
![]() |
T. W. Cline, D. Z. Rudner, D. A. Barbash, M. Bell, and R. Vutien Inaugural Article: Functioning of the Drosophila integral U1/U2 protein Snf independent of U1 and U2 small nuclear ribonucleoprotein particles is revealed by snf+ gene dose effects PNAS, December 7, 1999; 96(25): 14451 - 14458. [Abstract] [Full Text] [PDF] |
||||
![]() |
A Bhattacharya, S Sudha, H. Chandra, and R Steward flex, an X-linked female-lethal mutation in Drosophila melanogaster controls the expression of Sex-lethal Development, January 12, 1999; 126(23): 5485 - 5493. [Abstract] [PDF] |
||||
![]() |
D Bopp, C Schutt, J Puro, H Huang, and R Nothiger Recombination and disjunction in female germ cells of Drosophila depend on the germline activity of the gene sex-lethal Development, January 12, 1999; 126(24): 5785 - 5794. [Abstract] [PDF] |
||||
![]() |
I Sahut-Barnola and D Pauli The Drosophila gene stand still encodes a germline chromatin-associated protein that controls the transcription of the ovarian tumor gene Development, January 5, 1999; 126(9): 1917 - 1926. [Abstract] [PDF] |
||||
![]() |
S Hinson and R. Nagoshi Regulatory and functional interactions between the somatic sex regulatory gene transformer and the germline genes ovo and ovarian tumor Development, January 2, 1999; 126(5): 861 - 871. [Abstract] [PDF] |
||||
![]() |
C SchuLtt, A Hilfiker, and R Nothiger virilizer regulates Sex-lethal in the germline of Drosophila melanogaster Development, January 4, 1998; 125(8): 1501 - 1507. [Abstract] [PDF] |
||||