Analysis of the Gene Family Encoding Lipases in Candida rugosa by Competitive Reverse Transcription-PCR

摘要

Synthesis of multiple extracellular lipases in Candida rugosa has been demonstrated. However, it is difficult to characterize the expression spectrum of lip genes, since the sequences of the lip multigene family are very closely related. A competitive reverse transcription-PCR assay was developed to quantify the expression of lip genes. In agreement with the protein profile, the abundance of lip mRNAs was found to be (in decreasing order) lip1, lip3,lip2, lip5, and lip4. To analyze the effects of different culture conditions, the transcript concentrations for these mRNA species were normalized relative to the values for gpd, encoding glyceraldehyde-3-phosphate dehydrogenase. In relative terms, lip1 and lip3were highly and constitutively expressed (about 105molecules per μg of total RNA) whereas the other induciblelip genes, especially lip4, showed significant changes in mRNA expression under different culture conditions. These results indicate that differential transcriptional control oflip genes results in multiple forms of lipase proteins.