A group of lipoproteins with molecular sizes of approximately 30 kDa, referred to as 30K proteins, axe synthesized in fat body cells in the fifth instar larvae of silkworm, Bombyx mori. Analyzing the silkworm genome a...A group of lipoproteins with molecular sizes of approximately 30 kDa, referred to as 30K proteins, axe synthesized in fat body cells in the fifth instar larvae of silkworm, Bombyx mori. Analyzing the silkworm genome and its expressed sequence tags （ESTs）, we found 10 genes encoding 30K proteins, which are mainly distributed in three subfamilies. Of these, seven coding proteins were found to harbor the degrading sites of 30kP protease A, although the number of degrading sites may be different. As some potential core promoters and regulatory elements were supposed to be essential for gene transcription, the expression profiles of these genes were examined by semi-quantitative reverse transcription polymerase chain reaction. Eight 30K protein genes were detected to express luxuriantly in the fat body, while two were hardly expressed. Such results suggest that these 30K proteins may have different functions, and their adjacent regulatory elements play a crucial role in regulating their transcription.展开更多
基金This work was supported by the National Basic Research Program of China, the National Scientific and Technological Project and the National Natural Science Foundation under grant No. 2005 CB 121000, 2005 B A711A07 and 30471313, respectively.
文摘A group of lipoproteins with molecular sizes of approximately 30 kDa, referred to as 30K proteins, axe synthesized in fat body cells in the fifth instar larvae of silkworm, Bombyx mori. Analyzing the silkworm genome and its expressed sequence tags （ESTs）, we found 10 genes encoding 30K proteins, which are mainly distributed in three subfamilies. Of these, seven coding proteins were found to harbor the degrading sites of 30kP protease A, although the number of degrading sites may be different. As some potential core promoters and regulatory elements were supposed to be essential for gene transcription, the expression profiles of these genes were examined by semi-quantitative reverse transcription polymerase chain reaction. Eight 30K protein genes were detected to express luxuriantly in the fat body, while two were hardly expressed. Such results suggest that these 30K proteins may have different functions, and their adjacent regulatory elements play a crucial role in regulating their transcription.
