©Institute of Biochemistry and Cell Biology, SIBS, CAS Possible Effect of 30K Proteins in Embryonic Development

Abstract The silkworm Bombyx mori possesses a 30K protein family of 3×104 Da, the biological functions of which have not been fully identified. The relationship between the 30K protein family and the embryonic development of temperature sensitive sex-linked mutant strain of silkworm was investigated by two dimensional polyacrylamide gel electrophoresis (2D-PAGE) and Matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). The results show that protein spots 1–5 of the 30K protein family, mainly existing in normal strain, are possibly related to embryonic development. The early consumption of a 30K protein named 6G1-30K-1 and the accumulation of 30K proteins named 6G1-30K-3 and 6G1-30K-4 are likely caused by the destruction of physiological balance in normal embryonic development, which may lead to lower hatchability of the temperature sensitive strain. The results suggest that reasonable metabolism of 30K proteins is a prerequisite for the embryo’s normal development. Key words silkworm Bombyx mori; 30K protein; embryonic development; 2D-PAGE; MALDI-TOF MS The silkworm Bombyx mori is a holometabolic insect in lepidopteran with a characteristic of egg diapause. The embryo develops into the larva through 12 specific stages: (1) critical development I; (2) critical development II; (3