In:
Journal of Experimental Zoology, Wiley, Vol. 257, No. 2 ( 1991-02), p. 265-283
Abstract:
We have studied the protamines from different families of prosobranch gastropods. In those with external fertilization we find a simple pattern of sperm nuclear basic proteins, consisting of one major protamine. This protamine has between 75 and 105 amino acid residues in the ten species of the order Archaeogastropoda that we have examined. In six species of the order Patellogastropoda (Kozloff, Marine Invertebrates of the Pacific Northwest, Univ. of Wash. Press, Seattle, pp. 193–232, 1987), the protamine‐like component contains 220 ± 10 amino acid residues. However, the protamines from the archaeogastropod Monodonta turbinata and the patellogastropod Patella cerulea show a very similar amino acid composition. Cytochemically, four species of archaeogastropods and three species of patellogastropods show intermediate type 3 sperm basic proteins in the classification scheme of Bloch (Genetics 61: 93–111, 1969; Handbook of Genetics, Plenum, New York, pp. 136–167, 1976). The sperm basic protein profile in six internally fertilizing species of the orders Mesogastropoda and Neogastropoda is more complex since several protamine bands are found. In all cases the major protamines have high electrophoretic mobilities and the number of amino acid residues is estimated to be from 40 to 60. The combined set of major protamines in the mesogastropod Littorina neritoides and the neogastropod Murex brandaris display a similar amino acid composition that differs significantly from that in the externally fertilizing gastropods. In one mesogastropod and three neogastropod species cytochemical staining indicates the possible presence of type 2 stable protamines. Protamines from a neogastropod have a capacity for compacting DNA that is similar to that of an externally fertilizing archaeogastropod. We propose that changes in protamine features amongst different prosobranch gastropods are correlated with changes in nuclear condensation patterns and the fertilization biology of these mollusks.
Type of Medium:
Online Resource
ISSN:
0022-104X
,
1097-010X
DOI:
10.1002/jez.1402570217
Language:
English
Publisher:
Wiley
Publication Date:
1991
detail.hit.zdb_id:
2205981-7
detail.hit.zdb_id:
3181-1
SSG:
12
Permalink