Hermaphrodite hook up site
One such explanation that gained prominence was that the love dart existed as a nuptial gift of calcium for the mating partner, to be used for egg production (4, 14).
This was later disproved, because the amount of calcium in one dart is roughly equal to that of one egg, and thus it would not contribute significantly to an average clutch of 59 eggs (for ) (18).
Synthetic LDA also stimulated copulatory canal contractility.
Combined with our finding that the protein amino acid sequence resembles previously described molluscan buccalin precursors, this indicates that LDA is partially conserved in helicid snails and less in other molluscan species.
Acting as a hypodermic needle, the dart transfers an allohormone that increases paternity success.
Its precise physiological mechanism of action within the recipient snail is to close off the entrance to the sperm digestion organ via a contraction of the copulatory canal, thereby delaying the digestion of most donated sperm.
Helicid land snail copulation lasts 2–6 h and includes the unique use of calcareous (calcium carbonate) “love” darts that are pierced through the body wall of the mating partner during courtship (7–10).
Because the love darts alone do not increase paternity success, the mucus is implicated as a carrier of the active substance(s) (10).
We isolated LDA from extracts using bioassay-guided contractility measurement of the copulatory canal.
LDA is encoded within a 235-amino acid precursor protein containing multiple cleavage sites that, when cleaved, releases multiple bioactive peptides.
Love darts are characteristic features of the reproductive tract for the hermaphrodite land snail families of Helicidae and Ariophantidae (12).
These darts are assembled within a thick-walled dart sac and have now been described in numerous species, showing distinct species-specific structural architecture (17).