Disease relevance of SPADH1

• The structure of aSFP is almost identical to that of porcine spermadhesins PSP-I and PSP-II, which in turn show limited structural similarity with jellyroll topologies of certain virus capsid proteins [1].

High impact information on SPADH1

• The pig contains five closely linked spermadhesin genes, whereas only two spermadhesin genes are present in the cattle genome [2].
• We report here the genomic organization of the porcine spermadhesin gene cluster as well as a detailed comparative analysis with respect to other mammalian species [2].
• Crystallization and preliminary X-ray diffraction studies of aSFP, a bovine seminal plasma protein with a single CUB domain architecture [3].
• To determine the three-dimensional structure of aSFP, the protein was crystallized at 21 degrees C by vapor diffusion in hanging drops, using ammonium sulfate, pH 4.7, and polyethyleneglycol 4,000 as precipitants, containing 10% dioxane to avoid the formation of clustered crystals [3].
• However, in their respective seminal plasmas, the BSP and the HSP proteins associate into 90-150-kDa oligomeric complexes, whereas pB1 forms a 35-40-kDa complex with spermadhesin AQN-1 [4].

Biological context of SPADH1

• The binding site of aSFP was restricted to a thin coat at the apical part of the acrosomal cap [5].
• Here, we have investigated the topographical distribution and fate of bovine spermadhesin aSFP during sperm capacitation in order to assess whether aSFP could be involved in similar aspects of the fertilization process as its boar homologous proteins [5].
• A dose-dependent inhibition of lipid peroxidation could be demonstrated for medium and high concentrations of aSFP (0.125 to 4 g/l) [6].
• Compared with other reducing agents, aSFP showed the highest potency in preventing oxidative stress [6].
• Acidic seminal fluid protein (aSFP) is a major 13 kDa protein isolated from bull seminal plasma and characterized as a new growth factor which stimulates in vitro cell division and progesterone secretion by ovarian cells [7].

Anatomical context of SPADH1

• Acidic seminal fluid protein (aSFP, 12.9 kDa), a major protein of bull seminal plasma, belongs to the spermadhesin protein family [5].
• The amount of aSFP in swim-up sperm was 1.8 +/- 1.0 x 10(6) molecules/spermatozoa, but decreased dramatically to 22 +/- 10 x 10(3) and to undetectable levels after incubation of sperm for 1.5 h and 18 h, respectively, in capacitation medium [5].
• We suggest that in the bull aSFP may play a role in the regulation of sperm metabolism and the protection of sperm membranes from oxidative damage [6].
• According to this sequence, aSFP appears to represent a hitherto unknown protein. aSFP stimulated cell division and progesterone secretion of bovine granulosa cells in vitro in a potent and dose dependent manner. aSFP appears to be a potent growth factor with effects on ovarian granulosa cells [8].
• Ram spermadhesin and RSP proteins interact with heparin but only RSP proteins bind to hen's egg yolk low-density lipoprotein [9].

Associations of SPADH1 with chemical compounds

• 1. These results indicate that native aSFP possesses two pairs of cysteine residues of different reactivity [7].
• None spermadhesin of either gel-filtration fraction bound to a phosphorylcholine affinity matrix [10].

Analytical, diagnostic and therapeutic context of SPADH1

• Using isoelectric focusing in combination with sulfhydryl group-specific blotting, the three forms of aSFP were identified as completely oxidized (pI 4.7), partly reduced (pI 4.8) and fully reduced at pI 5 [7].
• There is one aSFP molecule per asymmetric unit, which corresponds to a crystal volume per unit molecular mass of 2.04 A3/Da, and analytical ultracentrifugation analysis show that aSFP is a monomeric protein [3].
• SDS-PAGE of fraction B indicated the presence of a 15.5 kDa protein, which is the major protein of ram seminal plasma (approximately 45% of total protein by weight) and was identified as a spermadhesin by N-terminal sequencing [9].

References