The Expression Of Glycoside Hydrolase Gene Of Musca Domestica Induced By Straw And The Screening Of Enteric Lignocellulose Microorganism

Objective:The aim of this work was to learn the digestion of straw from Musca domestica and the expression of lignocellulose hydrolase gene under different conditions, then isolated microorganisms from the tract of the Musca domestica. It lays a scientific foundation to housefly insects to rational utilize and develop biomass energy, which are important on exploitation of insect in the 21 st century. Methods: 1. With 30% wheat bran sorghum straw powder, 30% wheat bran wheat straw powder and pure wheat bran feeding housefly larvae respectively, we tested the contents of crude protein, crude fat, total sugar, total sugar, cellulose, lignin and hemicellulose before and after feeding and the control group. At the same time,we observed three experimental groups of larvae, 3rd instar larvae weight, pupal stage,emergence rate, adult survival duration, male and female ratio. 2. To explore the reliability of the reference gene GAPDH of Musca domestica under different forages,developmental stages and different tissues at the transcription and translation levels.The 2.5g pure lignin, cellulose, and xylan(hemicellulose) were dissolved in 20 ml sterilized water,(cellulose was 95% purity of the absorbent cotton and 78.6% of Vinda roll paper, xylan is the main component of semicellulose), then mixed them in humidity of wheat bran(50g dry weight) for feeding housefly to observe the differences expression of BG, BGL, LAC, MAN. Using pure sorghum straw, wheat straw instead of wheat bran to feed housefly to observe differential expression of genes mentioned aboved in housefly during passage. 3. Using pure wheat bran,sorghum straw, wheat straw feeding housefly larvae, fungi and bacteria were screened by cellulose Congo red medium, lignin medium and xylanase under aerobic and anaerobic conditions, then observe the morphology and quantity of colonies indifferent feeding groups. Results: 1.The total sugar, cellulose, lignin and hemicellulose content in the control group and after-feeding were decreased before-feeding(P<0.05). The crude fat content in each group was increased compared with before treatment(P<0.05); the crude protein content increased before feeding in most cases(P<0.05) except the crude protein content increased in before-feeding. 2.The transcription and translation levels of the GAPDH gene were stable in developmental stages, different tissues, and breeding larvae with different forages. 3.Using sorghum straw powder, wheat straw powder and wheat bran reared housefly respectively, we found that larvae stage, pupae period, the eclosion rate, adult survival period and 3 instar larva weight had significant difference(P<0.05), but the proportion of male and female was 1:1. 4. Using different components of lignocellulose fed housefly, BG, BGL, LAC, MAN gene of Musca domestica showed increased, but the increase rate were different. 5. Using pure sorghum straw, wheat straw instead of wheat bran which was control group fed housefly, the expression of those genes in sorghum straw and wheat straw group showed up(P<0.05), but different genes increased in different feed generation and the trend were different. 6. The number of aerobic fungi which cand igest lignocellulose was larger than that of anaerobic fungi;the amount of bacteria were greater than the number of fungi. The number of aerobic and anaerobic cellulose decomposing fungi were sorghum straw>wheat bran>wheat straw(P<0.05); The number of bacteria and fungi which breaks down lignin were sorghum stalk group> wheat straw > wheat bran(P<0.05); The number of bacteria and fungi which digested hemicellulose were wheat straw group> sorghum stalk group> wheat bran group. Conclusion: 1. Musca domestica can digest lignocellulose;the expression of glycoside hydrolase genes mentioned above had significantly increased and those genes got passaged; 2. There were microorganisms that can use lignocellulose in the digestive system of housefly. Feeding by different straw treatment, the microorganism communities had significant spatial heterogeneity consisted in the digestive system of housefly.