The synthesis of RNA and silk protein in Galleria mellonella silk glands.

The silk protein synthesis in silk glands of Galleria mellonella is preceded by the increase of total RNA content. The levels of the main RNA classes: 28S and 18S rRNA, tRNA as well as poly(A) + RNA change proportionally to the total RNA pool of glands. The fibroin-like silk protein of molecular weight of about 240 000 is characterized by the high content of four amino acids: glycine, alanine, serine and leucine, which account for more than 70% of amino acid residues. This fibroin-like protein is present in the posterior, middle and anterior parts of silk gland of the last instar larvae.