A Kinase Anchor Proteins ; genetics ; metabolism ; Animals ; Cell Cycle Proteins ; genetics ; metabolism ; Humans ; Neoplasms ; genetics ; metabolism

One of the most common causes of male infertility is asthenospermia, whose pathogenesis, however, is not yet clear. Recent researches have found that some genes (such as tektin-2, DNAI1, DNAH5, DNAH11, AKAP4, SEPT4 and Smcp) and proteins (such as sperm proteins ACTB, ANXA5, PRM1, PRM2 and SABP and seminal proteins Tf, PSA, PAP and Fractalkine) are associated with asthenospermia. The finding of these molecular markers has provided a base for the explanation of the molecular mechanism of asthenospermia, and these markers may become the diagnostic and therapeutic targets of the disease.
A Kinase Anchor Proteins ; genetics ; Animals ; Asthenozoospermia ; genetics ; metabolism ; Cytoskeletal Proteins ; genetics ; DNA Methylation ; genetics ; GTP Phosphohydrolases ; genetics ; Humans ; Male ; Mutation ; Septins

AIMTo perform screening, related to A-kinase anchoring proteins 4 (AKAP4) and tubulin proteins, in spermatozoa with absent or severely reduced motility in order to detect the status of the fibrous sheath and the axonemal structure.

METHODSAn immunocytochemical study of tubulin, used as a positive control, and AKAP4 was carried out to detect the presence and the distribution of these proteins in different sperm samples. The morphological characteristics of sperm were studied by transmission electron microscope (TEM) and the results were elaborated using a formula reported in previous studies. PCR was carried out on DNA extracted from peripheral blood lymphocytes to analyse partial sequences of the Akap4 and Akap3 genes.

RESULTSImmunolabelling of tubulin and AKAP4 showed different patterns, which led us to divide the patients into groups. In group I, the absence of AKAP4 and tubulin was revealed, although these patients did not show alterations in the Akap4/Akap3 binding site. TEM evaluation highlighted that a high presence of necrosis was associated with total sperm immotility. In group II, a regular AKAP4 and tubulin signal was present, although motility was reduced and TEM analysis revealed the presence of immaturity. In group III, in which a weak AKAP4 label associated with normal tubulin staining and reduced motility was observed, a severe disorganization of the fibrous sheath was highlighted by TEM.

CONCLUSIONWhile the role of AKAP4 in sperm motility is unclear, absent or weak AKAP4-labelling seems to be associated with absent or weak sperm motility.

A Kinase Anchor Proteins ; Humans ; Infertility, Male ; genetics ; physiopathology ; Male ; Microscopy, Electron ; Polymerase Chain Reaction ; Protein Precursors ; genetics ; metabolism ; Semen ; physiology ; Sperm Motility ; Spermatozoa ; physiology ; ultrastructure ; Tubulin ; genetics ; metabolism

The integrity of blood vessels controls vascular permeability and extravasation of blood cells, across the endothelium. Thus, the impairment of endothelial integrity leads to hemorrhage, edema, and inflammatory infiltration. However, the molecular mechanism underlying vascular integrity has not been fully understood. Here, we demonstrate an essential role for A-kinase anchoring protein 12 (AKAP12) in the maintenance of endothelial integrity during vascular development. Zebrafish embryos depleted of akap12 (akap12 morphants) exhibited severe hemorrhages. In vivo time-lapse analyses suggested that disorganized interendothelial cell-cell adhesions in akap12 morphants might be the cause of hemorrhage. To clarify the molecular mechanism by which the cell-cell adhesions are impaired, we examined the cell-cell adhesion molecules and their regulators using cultured endothelial cells. The expression of PAK2, an actin cytoskeletal regulator, and AF6, a connector of intercellular adhesion molecules and actin cytoskeleton, was reduced in AKAP12-depleted cells. Depletion of either PAK2 or AF6 phenocopied AKAP12-depleted cells, suggesting the reduction of PAK2 and AF6 results in the loosening of intercellular junctions. Consistent with this, overexpression of PAK2 and AF6 rescued the abnormal hemorrhage in akap12 morphants. We conclude that AKAP12 is essential for integrity of endothelium by maintaining the expression of PAK2 and AF6 during vascular development.
A Kinase Anchor Proteins/*genetics/metabolism ; Animals ; Blood Vessels/abnormalities/*embryology/metabolism ; Cell Cycle Proteins/genetics/metabolism ; Down-Regulation ; Embryo, Nonmammalian/abnormalities/*blood supply/embryology/metabolism ; Gene Deletion ; *Gene Expression Regulation, Developmental ; Hemorrhage/*embryology/genetics/metabolism ; Human Umbilical Vein Endothelial Cells ; Humans ; Intercellular Junctions/genetics/metabolism/ultrastructure ; Kinesin/genetics/metabolism ; Myosins/genetics/metabolism ; Zebrafish/*embryology/genetics ; p21-Activated Kinases/genetics/metabolism