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domains including MBOAT from residues 278- 499 (Hofmann et al., 2000), putative acyl-

CoA binding signature from residues R 102 - G 118 and putative active site catalytic residues
R 133 LIIEN 138 (Chi et al., 2014). The MBOAT domain is highlighted in green Figure 2(b)–(c),

acyl-CoA binding signature is marked with blue asterisk and the catalytic residues are
marked with red asterisks at the bottom of the multiple sequence alignment to get insight into

the conservation of these regions Figure 2(a). The alignment revealed that out of five indels
observed in various species Figure 2 (b–e), most of them were found to be associated with the

inter transmembrane regions while two indels were notably found in the Morus notabilis

were in the transmembrane region 8 and 9 as depicted in Figure 2(d-e), resulting in the loss of
two transmembrane regions as predicted by SMART domain analysis webserver

(http://smart.embl-heidelberg.de). However the two functional domains (MBOAT, acyl-

CoA binding signature) and the active site residues were found to be well conserved. Many
researchers have noticed variations in genes involved in fatty acid metabolism which leads to

increase as well as decrease in oil content (Zheng et al., 2008). An 81-bp insertion in
Arabidopsis DGAT1 gene resulting in the 27- aa tandem repeat leads to lowering of seed oil

content (Katavic et al., 1995). Notably, amino acid sequences from all the four species from
Euphorbiaceae family seemed to be very well conserved with the family and across other

families also. This indicates a well-conserved structure and function of DGAT1 protein

sequences from members of the Euphorbiaceae family including Euphorbia cotinifolia, the
candidate species for our experimental work (Atschul et al., 1990).

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