Journal of Biosciences

, Volume 32, Issue 2, pp 261–270

A homologue of the defender against the apoptotic death gene (dad1) in UV-exposed Chlamydomonas cells is downregulated with the onset of programmed cell death

  • Swati Moharikar
  • Jacinta S D’souza
  • Basuthkar J Rao
Article

DOI: 10.1007/s12038-007-0026-z

Cite this article as:
Moharikar, S., D’souza, J.S. & Rao, B.J. J Biosci (2007) 32: 261. doi:10.1007/s12038-007-0026-z

Abstract

We report here the isolation of a homologue of the potential anti-apoptotic gene, defender against apoptotic death (dad1) from Chlamydomonas reinhardtii cells. Using polymerase chain reaction (PCR), we investigated its expression in the execution process of programmed cell death (PCD) in UV-C exposed dying C. reinhardtii cells. Reverse-transcriptase (RT)-PCR showed that C. reinhardtii dad1 amplification was drastically reduced in UV-C exposed dying C. reinhardtii cells. We connect the downregulation of dad1 with the upregulation of apoptosis protease activating factor-1 (APAF-1) and the physiological changes that occur in C. reinhardtii cells upon exposure to 12 J/m2 UV-C in order to show a reciprocal relationship between proapoptotic and inhibitor of apoptosis factors. The temporal changes indicate a correlation between the onset of cell death and dad1 downregulation. The sequence of the PCR product of the cDNA encoding the dad1 homologue was aligned with the annotated dad1 (C_20215) from the Chlamydomonas database (http://genome.jgi-psf.org:8080/annotator/servlet/jgi.annotation.Annotation?pDb=chlre2); Annotation?pDb=chlre2); this sequence was found to show 100% identity, both at the nucleotide and amino acid level. The 327 bp transcript showed an open reading frame of 87 amino acid residues. The deduced amino acid sequence of the putative C. reinhardtii DAD1 homologue showed 54% identity with Oryza sativa, 56% identity with Drosophila melanogaster, 66% identity with Xenopus laevis, and 64% identity with Homo sapiens, Sus scrofa, Gallus gallus, Rattus norvegicus and Mus musculus.

Keywords

Chlamydomonas reinhardtiidefender against apoptotic death (dad1)UV-C

Abbreviations

APAF-1

apoptosis protease activating factor-1

dad1

defender against apoptotic cell death 1

IEP

isoelectric point

OST

oligosaccharyltransferase

PCD

programmed cell death

PCR

polymerase chain reaction

Copyright information

© Indian Academy of Sciences 2007

Authors and Affiliations

  • Swati Moharikar
    • 1
  • Jacinta S D’souza
    • 1
  • Basuthkar J Rao
    • 1
  1. 1.Department of Biological SciencesTata Institute of Fundamental ResearchColabaMumbai