Sponges aggregation factor

The ability of dissociated cells of sponges to aggregate with cells only of a like type (p. 29) depends upon large extracellular proteoglycans. That of Microciona prolifera appears to be an aggregate of about three hundred 35-kDa core protein molecules with equal masses of attached carbohydrate. This aggregation factor has a total mass of 2 x 104 kDa.226 227 It apparently interacts specifically, in the presence of Ca2+ ions, with a 210-kDa cell matrix protein to hold cells of the same species together.227... 

G. N. Misevic, J. Finne, and M. M. Burger, Involvement of carbohydrates as multiple low affinity interaction sites in the self-association of the aggregation factor from the marine sponge Microciona prolifera, J. Biol. Chem., 262 (1987) 5870-5877. 

The multi-step syntheses of disaccharide 8 and similar pyruvated saccharide fragments related to the aggregation factor of a marine sponge involved introduction of the pyruvate acetal groups without glycosidic bond cleavage by use of methyl pyruvate in the presence of BF3 etherate without added solvent. ... 

Muller, W.E.G., A. Bernd, R.K. Zahn, B. Kurelec, K. Dawes, I. Muller, and G. Uhlenbruck Xenograft Rejection in Marine Sponges. Isolation and Purification of an Inhibitory Aggregation Factor from Geodia cydonium. Eur. J. Biochem. 116, 573 (1981). 

Beads have been used to demonstrate that either intact aggregation factor or immobilized factor glycans can mediate the sponge cell aggregation [57, 67], that GAGs can bind to one another [39,44] and to demonstrate GSL-GSL interaction [72],... 

Ziegler, T. (1995) Synthesis of pyruvated saccharide fragments related to the aggregation factor of the marine sponge Microciona prolifera. 

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