Scavenger receptors (SRs) are transmembrane cell surface molecules recognized in apophotic cells, bacteria and lipopolysaccharide. With no physiological information on SRs in insects except SR-CI of Drosophila melanogaster, a putative SR gene was cloned and characterized in Spodoptera exigua. A partial S. exigua SR gene was obtained from hemocyte transcripts and exhibited high homology with type C. Its expression was confirmed in all developmental stages. Among different tissues, S. exigua SR was expressed highly in hemocytes. To confirm change in SR expression by infection, Escherichia coli was injected to fifth instar and RNA was extracted after 10 hours. SR expression in hemocytes of E. coli injected larva was not significantly different from the control but SR expression in fat body of E. coli injected larva was higher than the control. It is expected that SRs of S. exigua are related with immune responses against bacteria such as E. coli. To address its function, S. exigua SR expression was suppressed by double-stranded RNA (dsRNA).

The black soldier fly (BSF), Hermetia illucens, is known as a beneficial insect and feeds on organic materials derived from animals and human, resulting in reduction of food waste and conversion of organic materials. Despite of a lot of study about the BSF, there is a less information about composition of digestive enzyme of the BSF larva. Experimentally, there is no evidence about characterization of digestive enzyme of the BSF. We investigated biochemical property of digestive enzyme released from the salivary and gut of the BSF. Through digestive enzyme assay, we found that the BSF has amylase, lipase and protease activity in gut extracts, resulting in that the BSF belong to polyphagous insect group. In the BSF gut, trypsin-like protease activity showed one peak at various temperature and pH condition. This result means the BSF has probably a similar form of trypsin-like enzymes. On study of comparison of enzyme activity between the BSF and the housefly using the apiZYM kit, the BSF had more strongly digestive enzyme activity than one of the housefly about leucine arylamidase, alpha-galactosidase, beta-galactosidase, alpha-mannosidase and alpha-fucosidase. This finding supports that the BSF can ingest raw waste far more efficiently than any other known species of fly as reported previously.

체외수정 후 체외배양48시간에 난구세포의 제거 유ㆍ무에 따라 CR/sub 1aa/ 배양액에 homoglobin을 0, 1, 5 ㎍/㎖를 첨가한 구의 상실배기 이상 체외발육성 적은 난구세포를 제거한 구에서 23.8%, 33.3% 및 26.8% 였으며, 난구세포를 제거하지 않은 구에서는 각각 39.5%, 54.8% 및 48.8%로서 난구세포를 제거하지 않은 구에 Hb를 1 ㎍/㎖를 첨가한 구가 여타구보다 통계적으로 높은 결과를 얻었다(P<0.05). 체외수정 후 체외배양 96시간 후 난구세포를 제거 유ㆍ무에 따라 Hb를 0, 1, 5 ㎍/㎖를 첨가하였을 때, 상실배기 이상 체외발육성적은 난구세포를 제거한 구에서 각각 28.6%, 46.2% 및 39.1%였으며, 난구세포를 제거하지 않은 구에서는 각각 33.9%, 67.2% 및 46.0%로서, 난구세포를 제거하지 않은 구에 Hb를 1 ㎍/㎖를 첨가구가 여타구에 비해 통계적으로 유의하게 높게 나타났다(P<0.05). CR/sub 1aa/ 배양액에 L-NAME를 0, 10, 50 및 100 mM을 첨가한 구에서 상실배 이상 발육된 체외발육성적은 각각 55.6%, 64.9%, 58.8% 및 66.7%로써 L-NAME 첨가구가 무첨가구에 비해 커다란 차이가 나타나지 않았다(P>0.05). 모든 처리구에 배반포까지 발육된 체외수정란의 세포수에는 커다란 차이가 인정되지 않았다.

The mushroom Coriolusversicolor contains biologically active polysaccharides, most of which belong to the β glucan group. Diverse physicochemical properties, due to different sources and isolated types of β-glucans, may induce distinct biological activities. Here, we examined the effects of β-glucan from Coriolusversicolor (CVG) on the scavenger receptor B1 (SR-B1) expression and the role of SR-B1 in CVG-induced phagocytosis regulation by using SR-B1-specific shRNA transfected cells. We also examined whether Dectin-1 and CK2 are involved in SR-B1 expression in CVG-treated cells. Our study results showed that CVG increased the SR-B1 expression via Dectin-1 and CK2 in macrophages. However, the inhibition of SR-B1 expression by shRNA did not completely eliminate the effect of CVG on the increase of phagocytosis suggesting that SR-B1 is not essential for CVG-stimulated phagocytosis. This study will contribute to identify CVG's mechanism of action and its use in the development of functional foods.