title: Involvement of a gelsolin-related protein in spermatogenesis of the earthworm Lumbricus terrestris.
abstract: A gelsolin-related protein was isolated from seminal vesicles of the annelid Lumbricus terrestris. Compared with the isoforms of the gelsolin-related protein previously found in the muscle of the annelid body wall, the isolated protein was assigned to the first isoform (EWAM-P1) because of its electrophoretic mobility, chromatographic elution behaviour, immunological cross-reactivity and identical nucleotide sequence of segments obtained by reverse transcription/polymerase chain reaction. Immunofluorescence studies with smear preparations of developing male germ cells revealed characteristic changes of the local distribution of actin and EWAM-P1 during spermatogenesis. These changes were correlated with the developmental transport processes and structural alterations. F-actin, as revealed by rhodamine-phalloidin staining, formed a toroid-shaped structure in cytoplasmic bridges connecting the germ cells to a central cytophore during the developmental stages. An actin antibody reacting with both G- and F-actin demonstrated that actin was concentrated at the proximal and distal parts of the spermatocytes. EWAM-P1 was also localized in these regions, with intense staining in the distal part of spermatocytes and young spermatids in which the Golgi complex and proacrosome resided. The anti-actin antibody further stained the periphery of the nucleus. This staining gradually reduced during sperm maturation and covered about half of the length of the nucleus in elongated spermatids. Co-localization of EWAM with actin implied a functional significance of this gelsolin-related protein for the rearrangement of the actin cytoskeleton during earthworm spermiogenesis.
authors.affiliation: Institut für Zoomorphologie, Zellbiologie und Parasitologie, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany.
authors.forename: Evelyn
authors.initials: E
authors.lastname: Krüger
authors.forename: Horst
authors.initials: H
authors.lastname: Hinssen
authors.forename: Jochen
authors.initials: J
authors.lastname: D'Haese
mesh_terms: D000199:Actins / Q000378:metabolism; D000818:Animals; D001483:Base Sequence; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D018260:Gelsolin / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D015151:Immunoblotting; D008297:Male; D008840:Microfilament Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D008856:Microscopy, Fluorescence; D008969:Molecular Sequence Data; D009835:Oligochaeta / Q000378:metabolism / Q000502:physiology*; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D029607:Seminal Vesicle Secretory Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D012669:Seminal Vesicles / Q000737:chemistry / Q000378:metabolism; D013087:Spermatids / Q000166:cytology / Q000378:metabolism; D013090:Spermatocytes / Q000166:cytology / Q000378:metabolism; D013091:Spermatogenesis / Q000235:genetics / Q000502:physiology*; D013093:Spermatogonia / Q000166:cytology / Q000378:metabolism
chemical_list: D000199:Actins; D002352:Carrier Proteins; C034037:F-actin-binding proteins; D018260:Gelsolin; D008840:Microfilament Proteins; D020033:Protein Isoforms; D029607:Seminal Vesicle Secretory Proteins