QUICK SEARCH:   [advanced] Author: Keyword(s):
Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents

This Article Full Text (PDF) References Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Ravid, T. Articles by Lubzens, E. Search for Related Content PubMed PubMed Citation Articles by Ravid, T. Articles by Lubzens, E. Social Bookmarking                         What's this?

Journal of Experimental Biology, Vol 202, Issue 13 1819-1829, Copyright © 1999 by Company of Biologists

JOURNAL ARTICLES

Lipid accumulation in the ovaries of a marine shrimp penaeus semisulcatus (de haan)

T Ravid, A Tietz, M Khayat, E Boehm, R Michelis and E Lubzens
Israel Oceanographic and Limnological Research, National Institute of Oceanography, PO Box 8030, Haifa 31080, Israel and Department of Biochemistry, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel. esther@oce.

By the end of oocyte development, the ovaries of Penaeus semisulcatus have accumulated almost equal amounts (approximately 16 mg lipid g-1 protein) of phospholipids and triacylglycerols. The phospholipids consist mainly of phosphatidylcholine (75-80 %) and phosphatidylethanolamine (20-25 %). Approximately 30 % of the total fatty acid content of both phospholipids and triacylglycerols is made up of polyunsaturated fatty acids. In fractions obtained by centrifugation of ovarian homogenates, most of the increase in levels of ovarian lipids during ovarian maturation was associated with an increase in triacylglycerol levels in the floating fat fraction and of phospholipids in the infranatant fraction. The presence of polyunsaturated fatty acids in the ovaries indicates the occurrence of lipid transport to the ovary during oocyte maturation. The gradual decrease in the relative abundance of polyunsaturated fatty acids as the ovaries matured supports previously published results suggesting intra-ovarian synthesis of saturated and mono-unsaturated fatty acids. Most of the lipids found in the female haemolymph (64.8 %) were recovered in the high-density lipoprotein fraction after density ultracentrifugation. The haemocyanin fraction recovered from this stage of fractionation contained substantial amounts of lipid (16.8 %) that could be removed by further sequential centrifugation at a higher NaBr density, leaving less than 0.9 % of the total haemolymph lipids associated with this fraction. While 16.2 % of the lipids were recovered from the very high-density lipoprotein fractions, these lipoproteins carried only 64-89 microg lipid mg-1 protein compared with 538.9 microg lipid mg-1 protein in the high-density lipoprotein fraction, indicating that the high-density lipoproteins are more likely to be the main transporters of lipids to the ovary. However, the contribution of very high-density lipoproteins to lipid transport cannot be ruled out at this stage. In this study, we present two models for lipid transport to the ovary based on the abundance of phospholipids and triacylglycerols in the haemolymph and on the amounts of polyunsaturated fatty acids accumulated within the ovary during vitellogenesis.
CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    Twitter    What's this?

This article has been cited by other articles:

				A. Walker, S. Ando, and R. F. Lee Synthesis of a High-Density Lipoprotein in the Developing Blue Crab (Callinectes sapidus) Biol. Bull., February 1, 2003; 204(1): 50 - 56. [Abstract] [Full Text] [PDF]

				Y. Fan, J. Chase, V. L. Sevala, and C. Schal Lipophorin-facilitated hydrocarbon uptake by oocytes in the German cockroach Blattella germanica (L.) J. Exp. Biol., March 15, 2002; 205(6): 781 - 790. [Abstract] [Full Text] [PDF]