Disease relevance of Acrv1

• The recombinant fusion protein containing MSA-63 protein fragment was produced in Escherichia coli and used to immunize female mice [1].

High impact information on Acrv1

• Proacrosin, the zymogen form of the serine protease acrosin, is located within the acrosomal vesicle of mammalian spermatozoa and has been suggested to be involved in the fertilization process [2].
• Altogether, these results provide a new hypothesis concerning sperm TRPC2 gating: TRPC2 activation may be due to modifications of its interaction with both junctate and IP3R, induced by depletion of calcium from the acrosomal vesicle [3].
• This ER protein may be incorporated into the acrosomal vesicle via the Golgi apparatus, without glycosylation, during spermiogenesis, and may play an important role in the regulation of cell functions such as sperm motility and acrosome reaction [4].
• Taken together, these data demonstrate the existence of at least two isoforms of hyaluronidase: a soluble form within the acrosomal vesicle which is released during acrosomal exocytosis and a GPI-linked form which is present on the surface of both acrosome-intact and acrosome-reacted sperm [5].
• Atomic force microscopy has been used to investigate changes in the plasma membrane overlying the head region of mammalian spermatozoa (bull, boar, ram, goat, stallion, mouse, and monkey) during post-testicular development, after ejaculation, and after exocytosis of the acrosomal vesicle [6].

Biological context of Acrv1

• The results of this study suggested that the molecular heterogeneity of MSA-63 protein isolated from mouse testis and sperm, is due to a series of post-translational modifications on a single gene product [7].
• Fab fragments derived from MSA-63, when present in insemination mixtures (0.5 mg/ml), inhibited (P < 0.01) primate sperm binding to homologous hemizonae (monkey, 9.6 +/- 3; human sperm 9.4 +/- 2) compared with matched hemizona controls (monkey, 117 +/- 29; human, 20.4 +/- 3) [8].
• In the middle of the open reading frame, the fox sequence shows unique sequences absent from both the human, baboon SP-10, and mouse MSA-63 sequences [9].
• Database searches with the deduced amino acid sequence of cFSA-Acr.1 revealed that the clone has high homology to both human and baboon sperm protein SP-10, and the mouse sperm protein, MSA-63 [9].
• The cDNA fragments of MSA-63 gene were cloned from mouse testis cDNA library by an immunoscreening method using polyclonal antisera specific for MSA-63 [1].

Anatomical context of Acrv1

• Through previous studies, it was established that most of these protein spots were actin-like molecules co-purified with MSA-63 protein from mouse testis [7].
• Upon adhesion to the zona pellucida or egg extracellular matrix, sperm undergo regulated exocytosis of the acrosomal vesicle [10].
• The localization of this enzyme activity was compared with that of acid phosphatase (ACPase), as detected by the cerium-based method, using beta-glycerophosphate as substrate: ACPase activity was completely absent from the Golgi complex, small vesicles, acrosomal vesicle and acrosome throughout the entire process of acrosomal formation [11].
• Surprisingly, rab7, a protein involved in lysosome/endosome trafficking was also found associated with the acrosomal vesicle during mouse spermiogenesis [12].
• Electron microscopy of testis sections revealed that deformations appeared already in round spermatids as distortion of the acrosomal vesicle and asymmetrical position of the acrosomal granule; in many elongating spermatids the proximal end had a flat or concave shape, and the acrosomes contained a translucent vesicle [13].

Other interactions of Acrv1

• MSJ-1 is also maintained in testicular and epididymal spermatozoa, where it sharply demarcates into two distinct cell areas; the outer surface of the acrosomal vesicle, and the centrosomal area [14].
• Our results indicate that cyritestin is transported to the forming acrosomal vesicle through the Golgi apparatus to become part of the acrosomal membrane [15].
• Knockdown of TDP-43 using small interfering RNA released the enhancer-blocking effect of the SP-10 insulator in a stable cell culture model [16].

Analytical, diagnostic and therapeutic context of Acrv1

• Using ELISA, antisera against GST-63 and computer-predicted antigenic synthetic peptides were shown to cross-react with affinity-isolated MSA-63 protein coated on microwells [7].
• By using a Western blot assay, two major protein bands of 22 and 32 kDa, respectively were commonly detected on mouse testis homogenate strips by both anti-MSA-63 and anti-GST-63 [7].
• Electron microscopy and indirect immunofluorescence localized the site of Ds-1 and Ds-2 proteins inside the acrosomal vesicle [17].

References