Print version ISSN 0074-0276
Mem. Inst. Oswaldo Cruz vol.82 suppl.3 Rio de Janeiro 1987
The roles of haemolymphatic lipoproteins in the oogenesis of Rhodnius prolixusGondimKatia CalpOliveiraPedro Lagerblad deMasudaHatisaburo Universidade Federal do Rio de Janeiro, Departamento de Bioquímica Rio de Janeiro Brasil 0019878238992The fates of purified 32P-vitellin and 32P-lipophorin were followed in vitellogenic females of Rhodnius prolixus. While the radioactivity from 32P-vitellin 6 hours after injection was found almost exclusively in the ovary, the radioactivity from injected 32P-lipophorin was found distributed among several organs. In the ovary, the radioactivity from 32P-vitellin was associated with the contents of the yolk granules. 32P-lipophorin delivered a great amount of radioactive phospholipids to the ovary with no accumulation of its protein moiety, as observed after its iodination with 131I. The delivery of phospholipids was inhibited at 0ºC and by the metabolic inhibitors, sodium azide and sodium fluoride. Comparison of the radioactivity incorporation from 32P-lipophorin with that of 14C-inulin suggests that the 32P-phospholipids from lipophorin are not taken up by fluid phase endocytosis. The data presented here are compatible with the concept of lipophorin as a carrier of lipids in insects and provide evidence that lipophorin transports phospholipids as shown previously for other classes of lipids. The utilization by the oocytes of the phospholipids transported by lipophorin is discussed.Full text available only in PDF format.Texto completo disponível apenas em PDF.