Genetic Analysis of Viable Hsp90 Alleles Reveals a Critical Role in Drosophila Spermatogenesis

Corresponding author: Susan Lindquist, Howard Hughes Medical Institute, The University of Chicago, 5841 S. Maryland Ave., Box MC 1028, Chicago, IL 60637-1463., s-lindquist{at}uchicago.edu (E-mail)

Communicating editor: T. C. KAUFMAN

The Hsp90 chaperone protein maintains the activities of a remarkable variety of signal transducers, but its most critical functions in the context of the whole organism are unknown. Point mutations of Hsp83 (the Drosophila Hsp90 gene) obtained in two different screens are lethal as homozygotes. We report that eight transheterozygous mutant combinations produce viable adults. All exhibit the same developmental defects: sterile males and sterile or weakly fertile females. We also report that scratch, a previously identified male-sterile mutation, is an allele of Hsp82 with a P-element insertion in the intron that reduces expression. Thus, it is a simple reduction in Hsp90 function, rather than possible altered functions in the point mutants, that leads to male sterility. As shown by light and electron microscopy, all stages of spermatogenesis involving microtubule function are affected, from early mitotic divisions to later stages of sperm maturation, individualization, and motility. Aberrant microtubules are prominent in yeast cells carrying mutations in HSP82 (the yeast Hsp90 gene), confirming that Hsp90 function is connected to microtubule dynamics and that this connection is highly conserved. A small fraction of Hsp90 copurifies with taxol-stabilized microtubule proteins in Drosophila embryo extracts, but Hsp90 does not remain associated with microtubules through repeated temperature-induced assembly and disassembly reactions. If the spermatogenesis phenotypes are due to defects in microtubule dynamics, we suggest these are indirect, reflecting a role for Hsp90 in maintaining critical signal transduction pathways and microtubule effectors, rather than a direct role in the assembly and disassembly of microtubules themselves.

This article has been cited by other articles:

				J. S. Tash, R. Chakrasali, S. R. Jakkaraj, J. Hughes, S. K. Smith, K. Hornbaker, L. L. Heckert, S. B. Ozturk, M. K. Hadden, T. G. Kinzy, et al. Gamendazole, an Orally Active Indazole Carboxylic Acid Male Contraceptive Agent, Targets HSP90AB1 (HSP90BETA) and EEF1A1 (eEF1A), and Stimulates Il1a Transcription in Rat Sertoli Cells Biol Reprod, June 1, 2008; 78(6): 1139 - 1152. [Abstract] [Full Text] [PDF]

				A. Leskovar, H. Wegele, N. D. Werbeck, J. Buchner, and J. Reinstein The ATPase Cycle of the Mitochondrial Hsp90 Analog Trap1 J. Biol. Chem., April 25, 2008; 283(17): 11677 - 11688. [Abstract] [Full Text] [PDF]

				N. Wayne and D. N. Bolon Dimerization of Hsp90 Is Required for in Vivo Function: DESIGN AND ANALYSIS OF MONOMERS AND DIMERS J. Biol. Chem., November 30, 2007; 282(48): 35386 - 35395. [Abstract] [Full Text] [PDF]

				Y. Song, L. Fee, T. H. Lee, and R. P. Wharton The Molecular Chaperone Hsp90 Is Required for mRNA Localization in Drosophila melanogaster Embryos Genetics, August 1, 2007; 176(4): 2213 - 2222. [Abstract] [Full Text] [PDF]

				J. de la Torre, C. Lopez-Fernandez, M. Pita, J. L. Fernandez, S. D. Johnston, and J. Gosalvez Simultaneous Observation of DNA Fragmentation and Protein Loss in the Boar Spermatozoon Following Application of the Sperm Chromatin Dispersion (SCD) Test J Androl, July 1, 2007; 28(4): 533 - 540. [Abstract] [Full Text] [PDF]

				R. Basto, F. Gergely, V. M. Draviam, H. Ohkura, K. Liley, and J. W. Raff Hsp90 is required to localise cyclin B and Msps/ch-TOG to the mitotic spindle in Drosophila and humans J. Cell Sci., April 1, 2007; 120(7): 1278 - 1287. [Abstract] [Full Text] [PDF]

				F. Shinozaki, M. Minami, T. Chiba, M. Suzuki, K. Yoshimatsu, Y. Ichikawa, K. Terasawa, Y. Emori, K. Matsumoto, T. Kurosaki, et al. Depletion of Hsp90beta Induces Multiple Defects in B Cell Receptor Signaling J. Biol. Chem., June 16, 2006; 281(24): 16361 - 16369. [Abstract] [Full Text] [PDF]

				B. F. Mitchell, L. B. Pedersen, M. Feely, J. L. Rosenbaum, and D. R. Mitchell ATP Production in Chlamydomonas reinhardtii Flagella by Glycolytic Enzymes Mol. Biol. Cell, October 1, 2005; 16(10): 4509 - 4518. [Abstract] [Full Text] [PDF]

				C. C. Milton, P. Batterham, J. A. McKenzie, and A. A. Hoffmann Effect of E(sev) and Su(Raf) Hsp83 Mutants and Trans-heterozygotes on Bristle Trait Means and Variation in Drosophila melanogaster Genetics, September 1, 2005; 171(1): 119 - 130. [Abstract] [Full Text] [PDF]

				Y. Wang, R. Thuillier, and M. Culty Prenatal Estrogen Exposure Differentially Affects Estrogen Receptor-Associated Proteins in Rat Testis Gonocytes Biol Reprod, November 1, 2004; 71(5): 1652 - 1664. [Abstract] [Full Text] [PDF]

				R. Bagatell and L. Whitesell Altered Hsp90 function in cancer: A unique therapeutic opportunity Mol. Cancer Ther., August 1, 2004; 3(8): 1021 - 1030. [Abstract] [Full Text] [PDF]

				C. Rohmer, J. R. David, B. Moreteau, and D. Joly Heat induced male sterility in Drosophila melanogaster: adaptive genetic variations among geographic populations and role of the Y chromosome J. Exp. Biol., July 15, 2004; 207(16): 2735 - 2743. [Abstract] [Full Text] [PDF]

				H. Ecroyd, R. C. Jones, and R. J. Aitken Tyrosine Phosphorylation of HSP-90 During Mammalian Sperm Capacitation Biol Reprod, December 1, 2003; 69(6): 1801 - 1807. [Abstract] [Full Text] [PDF]

				S. Matsumoto, E. Tanaka, T. K. Nemoto, T. Ono, T. Takagi, J. Imai, Y. Kimura, I. Yahara, T. Kobayakawa, T. Ayuse, et al. Interaction between the N-terminal and Middle Regions Is Essential for the in Vivo Function of HSP90 Molecular Chaperone J. Biol. Chem., September 13, 2002; 277(38): 34959 - 34966. [Abstract] [Full Text] [PDF]

				N. Aoyagi and D. A. Wassarman Developmental and Transcriptional Consequences of Mutations in Drosophila TAFII60 Mol. Cell. Biol., October 15, 2001; 21(20): 6808 - 6819. [Abstract] [Full Text] [PDF]

				R. R. Snook, S. Y. Cleland, M. F. Wolfner, and T. L. Karr Offsetting Effects of Wolbachia Infection and Heat Shock on Sperm Production in Drosophila simulans: Analyses of Fecundity, Fertility and Accessory Gland Proteins Genetics, May 1, 2000; 155(1): 167 - 178. [Abstract] [Full Text]

				B. D. Johnson, A. Chadli, S. J. Felts, I. Bouhouche, M. G. Catelli, and D. O. Toft Hsp90 Chaperone Activity Requires the Full-length Protein and Interaction among Its Multiple Domains J. Biol. Chem., October 13, 2000; 275(42): 32499 - 32507. [Abstract] [Full Text] [PDF]

				G. M. Scholz, K. Cartledge, and N. E. Hall Identification and Characterization of Harc, a Novel Hsp90-associating Relative of Cdc37 J. Biol. Chem., August 10, 2001; 276(33): 30971 - 30979. [Abstract] [Full Text] [PDF]