Phagocytosis Of Trichoplusia Ni Cultured Cells To Nosema Bombycis And The Relationship With Spore Wall Protein

Nosema bombycis (Nb) is the first microsporidia known by people. Pebrine disease of silk worms caused by Nb threatened to devastate the silk industry. Nb not only allow horizontal transmission, but also allow transovarial transmission. Pebrine disease is the only quarantine disease in sericulture regions of the world.Clarifying the related factors of invasion into host cell contributes to in-depth study of the infection mechanisms of Nosema bombycis (Nb). In this study, we used the laser scanning confocal microscope to observe the distribution of Nb spores and the growth of Trichoplusia ni(Tn) cultured cells after 48h inoculated with Nb spores. Results showed Nb spores mainly gathered around the cell when Nb spores pretreated with 0.2mol/L potassium hydroxide was cultured by 48 h after inoculated into Tn cultured cells, and Nb spores scattered between the cells if Nb spores without pretreatment was cultured by 48 h after inoculated into Tn cultured cells. Through the SDS-PAGE of Tn cell cultures after inoculating Nb spores, we found there is a clear difference in total proteins if Nb spores was inoculated into Tn cultured cell after pretreatment. So we once again proved the phagocytosis of Tn cultured cells to 0.2mol/L potassium hydroxide pretreated Nb spores.Otherwise, through the analysis of the SDS-PAGE picture, we known 0.2mol/L potassium hydroxide treatment not only resulted in the missing and reduction of protein bands of 80 kD and 12 kD, but also leaded to the decrease of protein abundance of 30 kD. According to the aboved results, we guessed spore wall proteins (some or all) were decomposed and their structure changed after treatment, thus affecting the relationship between Nb spores and Tn cultured cells and promoting the phagocytosis of Tn cultured cells to Nb spores.