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germination. Triglycerides (TAGs) are a major storage form of energy and play an important

role in many physiological processes, particularly in seed oil accumulation, seedling
development and seed germination (Zhang et al., 2005). TAG production has great

socioeconomic impact in food, nutraceutical and industrial application. Thus numerous
conventional and molecular genetics strategies have been explored in attempts to increase

TAG content and modify the FA composition of plant seed oils (Lung and Weselake, 2006).
TAGs are synthesised by a series of enzymes in the Kennedy pathway leading to transfer of

acyl chains from acyl-CoAs to the sn-1, -2 and -3 positions of a glycerol backbone (Chen et

al., 2011, Ohlrogge and Browse, 1995). The final step of this pathway for acyl chain transfer
is catalysed by Diacylglycerol acyltransferase (DGAT) which is an integral endoplasmic

reticulum protein and has also been shown to be present in oil bodies and plastids (Chi et al.,

2014, Lung and Weselake, 2006). At least four categories of DGAT gene have been known to
exist with DGAT1 gene being found in many plant species. Both DGAT1 and its highly

homologous counterpart, the mammalian acyl-CoA/cholesterol acyltransferases (ACATs)
belong to a large family of membrane-bound O-acyltransferases (MBOAT) and divergence in

the amino acid sequence of DGAT1 have been found to impart substrate specificity to DAG
(Cases et al., 1998, Hobbs et al., 1999, Hofmann et al., 2000).

Therefore, in the current study, comparative analysis of available DAG1 amino acid

sequences from different angiospermic plant species was attempted to identify differences in
these genes at a protein level, which may lead to variation in lipid content and therefore oil

production. This attempt would pave a way for crop improvement of various energy crops
(Zheng et al., 2008; Sharma and Chauhan. 2012).

RESEARCH METHODOLOGY
In Silico Analysis

In Silico analysis of DGAT 1 genes responsible for triacylglycerol biosynthesis across

various members of energy crops was done by taking DGAT 1 protein sequence of Jatropha
as a reference. A well characterized plant DGAT 1 protein from Jatropha curcas (Gen Bank

accession number (ABB84383.1) was retrieved from the Uniprot database

(http://www.uniprot.org) in FASTA format. This protein sequence was then used for
protein BLAST (Altschul et al. 1990) homology search at NCBI BLAST Server

(http://blast.ncbi.nlm.nih.gov/Blast.cgi) against nr (non reductant) database. Homologous
sequences with identity >65% and e-value <0.0 for species across different plant families

(Euphorbiaceae, Solanaceae, Cucurbitaceae, Rutaceae, Fabaceae, Rosaceae, Araliaceae,
Malvaceae, Poaceae, Brassicaceae& Apiaceae) were retrieved and used to obtain multiple

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