Sperm with fibrous sheath dysplasia and anomalies in head-neck junction: focus on centriole and centrin 1.
Spermatozoa with a rare combination of two monomorphic sperm defects, dysplasia of the fibrous sheath (DFS) and alterations in head-mid-piece junction were analysed. The main focus was to explore the status of the centriole, a key organisation during fertilisation, using the centrin 1, a calcium-binding protein linked to this structure. The sperm quality was examined by light, scanning and transmission electron microscopy (SEM, TEM); immunocytochemistry was performed for tubulin, A-kinase anchor protein 4 (AKAP4) and centrin 1. Spermatozoa showed DFS defect associated with anomalies in head-tail attachment detected by SEM and TEM. Immunolocalisation of tubulin, AKAP4 and centrin 1 confirmed these alterations. Centrin 1 was visible in 67% of spermatozoa (in only 13% centrin localised in a normal position); in the majority of sperm centrin 1's location was altered, sometimes bent; often four spots, indicating the presence of two implantation fossae, were detected. At the centriolar level, immunoreactive fragments, frequently invading the entire short and thick tail, were observed. Centrin 1 is an essential component of the spermatozoa connecting piece and plays a role in centrosome dynamics during sperm morphogenesis and in zygotes and early embryos during spindle assembly. It is important to shed light on these rare conditions in order to better manage the patients during assisted reproductive technology.
Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy.
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Moretti
Rheumatology Unit, Azienda Ospedaliera Universitaria Senese, Siena, Italy.
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Pascarelli
Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy.
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Belmonte
Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy.
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Renieri
Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy.
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Collodel
D054758:A Kinase Anchor Proteins / Q000032:analysis; D000328:Adult; D002135:Calcium-Binding Proteins / Q000032:analysis*; D018797:Cell Cycle Proteins / Q000032:analysis*; D002502:Centrioles / Q000648:ultrastructure*; D006801:Humans; D007150:Immunohistochemistry; D007248:Infertility, Male / Q000473:pathology; D007558:Italy; D008297:Male; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D055101:Semen Analysis; D013077:Sperm Head / Q000648:ultrastructure*; D013082:Sperm Tail / Q000648:ultrastructure; D013094:Spermatozoa / Q000002:abnormalities* / Q000737:chemistry / Q000648:ultrastructure*; D014404:Tubulin / Q000032:analysis
D054758:A Kinase Anchor Proteins; C485480:AKAP4 protein, human; C580665:CETN1 protein, human; D002135:Calcium-Binding Proteins; D018797:Cell Cycle Proteins; D014404:Tubulin
centrin; dysplasia of the fibrous sheath; immunocytochemistry; sperm head-neck attachment; transmission electron microscopy