Crystallization and preliminary X-ray diffraction studies of aSFP, a bovine seminal plasma protein with a single CUB domain architecture

Dias, João M.; Carvalho, Ana Luı́sa; Kölln, Ingo; Calvete, Juan J.; Töpfer‐Petersen, Edda; Varela, Paloma F.; Romero, Antonio; Urbanke, Claus; Romão, Maria João

doi:10.1002/pro.5560060323

Cited by 8 publications

(3 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The recently determined three-dimensional CUB domain structure (20) agrees well with a ligand binding function. The CUB domain is a barrel-like structure containing two layers of five-stranded ␤-sheets with the ␤-turns in a surface-exposed position as in the antigen binding regions of immunoglobulins.…”

Section: Identification Of the Regions For Binding Of If-bsupporting

confidence: 61%

Molecular Dissection of the Intrinsic Factor-Vitamin B12 Receptor, Cubilin, Discloses Regions Important for Membrane Association and Ligand Binding

Kristiansen

Kozyraki

Jacobsen

et al. 1999

Journal of Biological Chemistry

116

View full text Add to dashboard Cite

Cubilin, the receptor for intrinsic factor-vitamin B 12 , is a novel type of high molecular weight receptor consisting of a 27 CUB (complement components C1r/C1s, Uegf, and bone morphogenic protein-1) domain cluster preceded by 8 epidermal growth factor repeats and a short N-terminal sequence. In addition to binding the vitamin B 12 -carrier complex, cubilin also binds receptor-associated protein. 1 depends on gastric intrinsic factor (IF), which undergoes a specific and strong complex formation with the vitamin in the intestinal lumen (1). The vitamin-carrier complex is subsequently internalized after being recognized by the high affinity membrane receptor, cubilin (2, 3). The binding of IF-B 12 is suggested to occur via the N-terminal region of IF (4) and only when B 12 is bound to the carrier protein (1-3, 5). The physiological importance of the specific B 12 carrier and its receptor is evident from the B 12 deficiency, characterized by the megaloblastic anemia and neurological symptoms related to defective functional expression of IF or cubilin (6 -11). In addition to binding IF-B 12 , cubilin also binds receptor-associated protein (RAP) (5), and growing evidence suggests that the receptor has other biological functions. This is in particular indicated by the fact that kidney and yolk sac epithelia exhibit a high cubilin expression (2, 5, 12), albeit IF is synthesized in the gastric epithelium and virtually only is present in the gastrointestinal lumen.The recent determination of the primary structure of the rat and human cubilin molecule (13, 14) revealed an ϳ3600-aa protein with a short N-terminal segment followed by 8 epidermal growth factor (EGF) repeats and a large cluster of 27 CUB 2 domains. No classical transmembrane segment has been predicted, and the overall structure is distinct from known endocytic receptors, including the RAP-binding members of the low density lipoprotein (LDL) receptor family (15). Two mutations, one causing a Pro/Leu substitution in CUB domain 8 and another suggested to activate an intronic cryptic splice site leading to truncation of the receptor in CUB domain 6, have recently been identified in the cubilin gene of patients with inherited B 12 malabsorption (11).To link the structural and functional features of cubilin, we established a comprehensive panel of transfected Chinese hamster ovary (CHO) cells expressing various segments of the receptor. Biochemical analyses of the cells and expression products now delineate the regions important for membrane association and binding of IF-B 12 and RAP. EXPERIMENTAL PROCEDURESLigands and Receptors-Porcine and human IF-B 12 were purified from gastric mucosa extract as described (16). Human RAP was produced as a recombinant protein in Escherichia coli. Rabbit cubilin was purified from renal cortex by IF-B 12 and RAP affinity chromatography, as described previously (5). Construction of Plasmids for Expression of Recombinant Rat CubilinFragments-Cubilin cDNA fragments extended with enzyme restriction sites were amplified by polymerase c...

show abstract

Section: Identification Of the Regions For Binding Of If-bsupporting

confidence: 61%

Molecular Dissection of the Intrinsic Factor-Vitamin B12 Receptor, Cubilin, Discloses Regions Important for Membrane Association and Ligand Binding

Kristiansen

Kozyraki

Jacobsen

et al. 1999

Journal of Biological Chemistry

116

View full text Add to dashboard Cite

show abstract

“…An exception are the spermadhesin molecules, which have been implicated in mediating sperm-egg envelope interactions in mammals [29,30]. Spermadhesins are composed of 109-133 amino acids, and thus are essentially a single CUB domain.…”

Section: Cub Domainsmentioning

confidence: 99%

Oviductin, the Xenopus laevis Oviductal Protease That Processes Egg Envelope Glycoprotein gp43, Increases Sperm Binding to Envelopes, and Is Translated as Part of an Unusual Mosaic Protein Composed of Two Protease and Several CUB Domains1

Lindsay

Wieduwilt

Hedrick

1999

Biology of Reproduction

View full text Add to dashboard Cite

The glycoprotein envelope surrounding the Xenopus laevis egg is converted from an unfertilizable to a fertilizable form during transit through the pars recta portion of the oviduct. Envelope conversion involves the pars recta protease oviductin, which selectively hydrolyzes envelope glycoprotein gp43 to gp41. Oviductin cDNA was cloned, and sequence analysis revealed that the protease is translated as the N terminus of an unusual mosaic protein. In addition to the oviductin protease domain, a protease domain with low identity to oviductin was present, possessing an apparent nonfunctional catalytic site. Three CUB domains were also present, which are related to the mammalian spermadhesin molecules implicated in mediating sperm-envelope interactions. We propose that during post-translational proteolytic processing of the mosaic oviductin glycoprotein, the processed N-terminal protease domain is released coupled to two C-terminal CUB domains and constitutes the enzymatically active protease molecule. In functional studies, isolated coelomic egg envelopes treated with oviductin purified from the oviduct showed a dramatic increase in sperm binding. This observation established that oviductin alone was the oviductal factor responsible for converting the egg envelope to a sperm-penetrable form, via an increase in sperm binding. Trypsin mimicked oviductin's effect on envelope hydrolysis and sperm binding, demonstrating that gp43 processing is the only requirement for envelope conversion.

show abstract

“…In a variety of mammals [1][2][3][4][5][6][7], birds, reptiles and amphibians [8][9][10], after mating sperm are stored in a portion of the female reproductive tract, called the sperm reservoir. The functional sperm reservoir in the mammalian lower oviduct, known as the isthmus, regulates sperm function and extends cell viability, traits necessary for high fertility in species like swine in which semen deposition and ovulation are not always well synchronized [11][12][13].…”

Section: Introductionmentioning

confidence: 99%

Adhesion to oviduct glycans regulates porcine sperm Ca2+ influx and viability

et al. 2020

View full text Add to dashboard Cite

Before fertilization, sperm bind to epithelial cells of the oviduct isthmus to form a reservoir that regulates sperm viability and capacitation. The sperm reservoir maintains optimum fertility in species, like swine, in which semen deposition and ovulation may not be well synchronized. We demonstrated previously that porcine sperm bind to two oviductal glycan motifs, a biantennary 6-sialylated N-acetyllactosamine (bi-SiaLN) oligosaccharide and 3-Osulfated Lewis X trisaccharide (suLe X). Here, we assessed the ability of these glycans to regulate sperm Ca 2+ influx, capacitation and affect sperm lifespan. After 24 h, the viability of sperm bound to immobilized bi-SiaLN and suLe X was higher (46% and 41% respectively) compared to viability of free-swimming sperm (10-12%). Ca 2+ is a central regulator of sperm function so we assessed whether oviduct glycans could affect the Ca 2+ influx that occurs during capacitation. Using a fluorescent intracellular Ca 2+ probe, we observed that both oviduct glycans suppressed the Ca 2+ increase that occurs during capacitation. Thus, specific oviduct glycans can regulate intracellular Ca 2+. Because the increase in intracellular Ca 2+ was suppressed by oviduct glycans, we examined whether glycans affected capacitation, as determined by protein tyrosine phosphorylation and the ability to undergo a Ca 2+ ionophore-induced acrosome reaction. We found no discernable suppression of capacitation in sperm bound to oviduct glycans. We also detected no effect of oviduct glycans on sperm motility during capacitation. In summary, Le X and bi-SiaLN glycan motifs found on oviduct oligosaccharides suppress the Ca 2+ influx that occurs during capacitation and extend sperm lifespan but do not affect sperm capacitation or motility.

show abstract

Crystallization and preliminary X-ray diffraction studies of aSFP, a bovine seminal plasma protein with a single CUB domain architecture

Cited by 8 publications

References 20 publications

Molecular Dissection of the Intrinsic Factor-Vitamin B12 Receptor, Cubilin, Discloses Regions Important for Membrane Association and Ligand Binding

Molecular Dissection of the Intrinsic Factor-Vitamin B12 Receptor, Cubilin, Discloses Regions Important for Membrane Association and Ligand Binding

Oviductin, the Xenopus laevis Oviductal Protease That Processes Egg Envelope Glycoprotein gp43, Increases Sperm Binding to Envelopes, and Is Translated as Part of an Unusual Mosaic Protein Composed of Two Protease and Several CUB Domains1

Adhesion to oviduct glycans regulates porcine sperm Ca2+ influx and viability

Contact Info

Product

Resources

About