Genetics, Vol 131, 905-916, Copyright © 1992

INVESTIGATIONS

Single Amino Acid Exchanges in Separate Domains of the Drosophila serendipity {delta} Zinc Finger Protein Cause Embryonic and Sex Biased Lethality

M. Crozatier, K. Kongsuwan, P. Ferrer, J. R. Merriam, J. A. Lengyel and A. Vincent
Centre de Recherche de Biochimie et de Genetique Cellulaires du CNRS 118, route de Narbonne, 31062 Toulouse Cedex, France

The Drosophila serendipity (sry) delta ({delta}) zinc finger protein is a sequence-specific DNA binding protein, maternally inherited by the embryo and present in nuclei of transcriptionally active cells throughout fly development. We report here the isolation and characterization of four ethyl methanesulfate-induced zygotic lethal mutations of different strengths in the sry {delta} gene. For the stronger allele, all of the lethality occurs during late embryogenesis or the first larval instar. In the cases of the three weaker alleles, most of the lethality occurs during pupation; moreover, those adult escapers that emerge are sterile males lacking partially or completely in spermatozoa bundles. Genetic analysis of sry {delta} thus indicates that it is an essential gene, whose continued expression throughout the life cycle, notably during embryogenesis and pupal stage, is required for viability. Phenotypic analysis of sry {delta} hemizygote escaper males further suggests that sry {delta} may be involved in regulation of two different sets of genes: genes required for viability and genes involved in gonadal development. All four sry {delta} alleles are fully rescued by a wild-type copy of sry {delta}, but not by an additional copy of the sry {beta} gene, reinforcing the view that, although structurally related, these two genes exert distinct functions. Molecular characterization of the four sry {delta} mutations revealed that these mutations correspond to single amino acid replacements in the sry {delta} protein. Three of these replacements map to the same (third out of seven) zinc finger in the carboxy-terminal DNA binding domain; interestingly, none affects the zinc finger consensus residues. The fourth mutation is located in the NH(2)-proximal part of the protein, in a domain proposed to be involved in specific protein-protein interactions.

This article has been cited by other articles:

				T. K. Smulders-Srinivasan and H. Lin Screens for piwi Suppressors in Drosophila Identify Dosage-Dependent Regulators of Germline Stem Cell Division Genetics, December 1, 2003; 165(4): 1971 - 1991. [Abstract] [Full Text] [PDF]

				H. Peng, L. Zheng, W.-H. Lee, J. J. Rux, and F. J. Rauscher III A Common DNA-binding Site for SZF1 and the BRCA1-associated Zinc Finger Protein, ZBRK1 Cancer Res., July 1, 2002; 62(13): 3773 - 3781. [Abstract] [Full Text] [PDF]

				F Payre, M Crozatier, and A Vincent Direct control of transcription of the Drosophila morphogen bicoid by the serendipity delta zinc finger protein, as revealed by in vivo analysis of a finger swap. Genes & Dev., November 15, 1994; 8(22): 2718 - 2728. [Abstract] [PDF]

				S Ibnsouda, F Schweisguth, G de Billy, and A Vincent Relationship between expression of serendipity alpha and cellularisation of the Drosophila embryo as revealed by interspecific transformation Development, January 10, 1993; 119(2): 471 - 483. [Abstract] [PDF]