Characterization of the main plasma lipoproteins from the ovoviviparous viperid snake Bothrops jararaca

Abstract

Plasma from estrogen treated males of Bothropsjararaca fractionated by ultracentrifugation showed three main fractions with very low density, intermediate density and high density, respectively. The very low density and high density fractions are mainly composed of lipoproteins detected by specific staining with Sudan Black. Electron microscopy of the very low density lipoproteins shows a single population of particles with a mean diameter of 29.6 nm similar to that of very low density lipoproteins from laying hens. The very low density lipoprotein of Bothrops jararaca is composed of two polypeptides with molecular masses of 450 and 20 kDa. Three main polypeptides are detected in the plasma high density fraction with molecular masses of 190, 160 and 110 kDa. Analysis of whole plasma proteins, from control and estrogen treated males, by sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed that the 20 kDa very low density lipoprotein polypeptide and the 160 and 110 kDa high density lipoprotein polypeptides are induced de novo after estrogen treatment. These results suggest that the two very low density lipoprotein polypeptides are the snake counterparts of chicken very low density polypepüdes. The estrogen induced high density lipoprotein polypeptides probably make up the vitellogenin(s) of Bothropsjararaca. An antiserum raised against the whole very low density plasma fraction was able to recognize only the two polypepüdes found in this fraction in the plasma of treated males. Using this anüserum, in a double immunodiffusion test, we were able to detect only a faint reaction against Bothrops jararaca egg yolk proteins.