Four intracellular genomes direct weevil biology: nuclear, mitochondrial, principal endosymbiont, and Wolbachia.

Cell physiology in the weevil Sitophilus oryzae is coordinated by three integrated genomes: nuclear, mitochondrial, and the "S. oryzae principal endosymbiont" (SOPE). SOPE, a cytoplasmic bacterium (2 x 10(3) bacteria per specialized bacteriocyte cell and 3 x 10(6) bacteria per weevil) that belongs to the proteobacteria gamma3-subgroup, is present in all weevils studied.

Molecular characterization of the principal symbiotic bacteria of the weevil Sitophilus oryzae: a peculiar G + C content of an endocytobiotic DNA.

The principal intracellular symbiotic bacteria of the cereal weevil Sitophilus oryzae were characterized using the sequence of the 16S rDNA gene (rrs gene) and G + C content analysis. Polymerase chain reaction amplification with universal eubacterial primers of the rrs gene showed a single expected sequence of 1,501 bp. Comparison of this sequence with the available database sequences placed the intracellular bacteria of S.

A molecular aspect of symbiotic interactions between the weevil Sitophilus oryzae and its endosymbiotic bacteria: over-expression of a chaperonin.

Specific proteins of symbiosis were analyzed by the comparison of two-dimensional electrophoresis protein patterns of symbiotic and aposymbiotic strains of the weevil Sitophilus oryzae. One protein was shown to be exclusively expressed in the aposymbiotic strain and three proteins, including a chaperonin, were characterized in the symbiotic strain pattern. The groE-like operon, encoding the two chaperonins groES and GroEL-like proteins of the endocytobiotes, was sequenced.

Presence of a protein specific of endocytobiosis (symbionin) in the weevil Sitophilus.

Chaperonins are ubiquitous proteins found in all prokaryotic and eukaryotic cells. They are overproduced in several parasitic bacteria and are implicated in at least 2 types of endocytobiosis: in amoebae and in aphids. This work puts in evidence that a protein named symbionin, which shows an immunological homology with the E.

Characteristics and development of the tyrosine-rich protein granules in the adipose tissue of the Curculionid beetle Sitophilus oryzae.

In the Curculionid beetle Sitophilus oryzae, the fat body is composed of one type of adipocyte, interstitial cells and oenocytes. Synthesis and storage of tyrosine-rich-protein granules (TRPG) in adipocytes are observed during all the larval and prepupal stages (except the first larval instar which has not been studied). They appear first in the posterior part of the fat body, around the nucleus of adipocytes.