Spatiotemporal association of DNAJB13 with the annulus during mouse sperm flagellum development.
BMC Dev Biol
; 9: 23, 2009 Mar 19.
Article
in En
| MEDLINE
| ID: mdl-19298648
BACKGROUND: The sperm annulus is a septin-based fibrous ring structure connecting the midpiece and the principal piece of the mammalian sperm flagellum. Although ultrastructural abnormalities and functional importance of the annulus have been addressed in Sept4-null mutant mice and a subset of human patients with asthenospermia syndrome, little is known about how the structure is assembled and positioned to the midpiece-principal piece junction during mammalian sperm flagellum development. RESULTS: By performing immunofluorescence and biochemical approaches with antibodies against DNAJB13 and an annulus constituent SEPT4, we report here a spatiotemporal association of DNAJB13 with sperm annulus during mouse sperm flagellum development. DNAJB13 co-localized with SEPT4 to the annulus, and both were first able to be detected in step 9 spermatids. As spermiogenesis proceeded, the annular DNAJB13 immunosignal increased until the annulus reached the midpiece-principal piece junction, and then gradually disappeared from it in late spermiogenesis. In contrast, the SEPT4 immunosignal was relatively unaltered, and still present on annulus of mature spermatozoa. In Sept4-null mouse spermatids lacking the annulus structure, the annulus-like DNAJB13 immunosignal was still able to be detected, albeit weaker, at the neck region of the flagella. In vitro DNAJB13 was co-localized and interacted with SEPT4 directly. CONCLUSION: The direct interaction of DNAJB13 with SEPT4 in vitro and its spatiotemporal association with the annulus during sperm flagellum development, and even its annulus-like appearance in the annulus-deficient spermatids, suggest that DNAJB13 may be involved in assembling the annulus structure and positioning it towards the midpiece-principal piece junction.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Sperm Tail
/
Cytoskeletal Proteins
/
HSP40 Heat-Shock Proteins
/
GTP Phosphohydrolases
Type of study:
Risk_factors_studies
Limits:
Animals
/
Female
/
Humans
/
Male
Language:
En
Journal:
BMC Dev Biol
Journal subject:
EMBRIOLOGIA
Year:
2009
Document type:
Article
Affiliation country:
Suecia
Country of publication:
Reino Unido