Journal of Biosciences

, Volume 27, Issue 2, pp 105–112 | Cite as

Genes encoding chimeras ofNeurospora crassa erg-3 and human TM7SF2 proteins fail to complement Neurospora and yeast sterol C-14 reductase mutants



The human gene TM7SF2 encodes a polypeptide (SR-1) with high sequence similarity to sterol C-14 reductase, a key sterol biosynthetic enzyme in fungi, plants and mammals. In Neurospora and yeast this enzyme is encoded by theerg-3 anderg24 genes respectively. In an effort to demonstrate sterol C-14 reductase activity for SR-1 we constructed six recombinant genes coding for chimeras of the Neurosporaerg-3 and SR-1 protein sequences and tested them for complementation of the Neurosporaerg-3 mutant. To our surprise, all the chimeras failed to complementerg-3. A few of the chimeric proteins were also tested against the yeasterg24 mutant, but again there was no complementation. We discuss some reasons that might account for these unexpected findings


Lamin B receptor sterol reductase 

Abbreviations used


carboxyl terminal domain


lamin B receptor


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Copyright information

© Indian Academy of Sciences 2002

Authors and Affiliations

  1. 1.Centre for Cellular and Molecular BiologyHyderabadIndia

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