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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

  • A. Prakash
  • Durgadas P. Kasbekar
Article

Abstract

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

Keywords

Lamin B receptor sterol reductase 

Abbreviations used

CTD

carboxyl terminal domain

LBR

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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