Tissue-specific expression of the heat shock protein HSP27 during Drosophila melanogaster development.
The alpha-crystallin-related heat shock (stress) protein hsp27 is expressed in absence of heat shock during Drosophila melanogaster development. Here, we describe the tissue distribution of this protein using an immunoaffinity-purified antibody. In embryos, hsp27 translated from maternal RNA is uniformly distributed, except in the yolk. During the first, second, and early third larval stages, hsp27 expression is restricted to the brain and the gonads. These tissues are characterized by a high level of proliferating cells. In late third instar larvae and early pupae, in addition to the central nervous system and the gonads, all the imaginal discs synthesize hsp27. The disc expression seems restricted to the beginning of their differentiation since it disappears during the second half of the pupal stage: no more hsp27 is observed in the disc-derived adult organs. In adults, hsp27 is still present in some regions of the central nervous system, and is also expressed in the male and female germ lines where it accumulates in mature sperm and oocytes. The transcript and the protein accumulate in oocytes since the onset of vitellogenesis with a uniform distribution similar to that found in embryos. The adult germ lines transcribe hsp27 gene while no transcript is detected in the late pupal and adult brain. These results suggest multiple roles of hsp27 during Drosophila development which may be related to both the proliferative and differentiated states of the tissues.
Department of Molecular Biology, University of Geneva, Switzerland.
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Pauli
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CH
Tonka
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Tissieres
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AP
Arrigo
D000818:Animals; D002846:Chromatography, Affinity; D004331:Drosophila melanogaster / Q000196:embryology* / Q000378:metabolism; D006360:Heat-Shock Proteins / Q000096:biosynthesis* / Q000235:genetics; D007106:Immune Sera / Q000302:isolation & purification; D007150:Immunohistochemistry; D007814:Larva / Q000378:metabolism; D009693:Nucleic Acid Hybridization; D009928:Organ Specificity; D011679:Pupa / Q000378:metabolism; D012313:RNA; D016372:RNA, Antisense; D013997:Time Factors; D014158:Transcription, Genetic
D006360:Heat-Shock Proteins; D007106:Immune Sera; D016372:RNA, Antisense; D012313:RNA