The complete primary structure of the spermadhesin AWN, a zona pellucida-binding protein isolated from boar spermatozoa.
AWN is a boar protein which originates in secretions of the male accessory glands and which becomes sperm surface-associated upon ejaculation. It is one of the components thought to mediate sperm adhesion to the egg's zona pellucida through a carbohydrate-recognition mechanism. AWN may, thus, participate in the initial events of fertilization in the pig. In this report we describe its complete primary structure by combination of protein-chemical and mass spectrometric methods. AWN exists as two isoforms, AWN-1 and AWN-2, which differ in that AWN-2 is N-terminally acetylated. The amino acid sequence of AWN contains 133 amino acid residues and two disulphide bridges between nearest-neighbour cysteine residues. Analysis of the amino acid sequence of the AWN proteins showed significant similarity only to AQN-1 and AQN-3, two other boar spermadhesins.
Sanz
L
L
Dermatologische Klinik, Andrology Unit, München, Germany.
Calvete
J J
JJ
Mann
K
K
Schäfer
W
W
Schmid
E R
ER
Amselgruber
W
W
Sinowatz
F
F
Ehrhard
M
M
Töpfer-Petersen
E
E
D000595:Amino Acid Sequence; D000818:Animals; D002352:Carrier Proteins / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D005260:Female; D008297:Male; D008969:Molecular Sequence Data; D011485:Protein Binding; D029589:Seminal Plasma Proteins; D013084:Sperm-Ovum Interactions / Q000187:drug effects; D013094:Spermatozoa / Q000737:chemistry*; D013329:Structure-Activity Relationship; D013552:Swine; D015044:Zona Pellucida / Q000737:chemistry*
D002352:Carrier Proteins; D029589:Seminal Plasma Proteins; C425042:spermadhesin