Among the most abundant lipid droplet protein observed in our
study and in Zhang et al. [21] was the MDT-28 protein. This protein contains
a conserved Perilipin domain in the N terminus, suggesting that
MDT-28 is an important structural lipid droplet protein that may play
similar structural roles to conserved perilipins. In mammals, perilipins
regulate the balance between lipid storage and lipid hydrolysis [10].
The region of homology of MDT-28 to perilipin is in the relatively
small region of the protein, identified as a perilipin domain. Interestingly,
knockdown of MDT-28 by RNAi had several disparate effects on
C. elegans lipid droplets. We found that intestinal lipid droplet were
somewhat reduced in MDT-28 knockdowns, but lipid droplets in oocytes
and embryos appeared to be clustered and showed brighter Nile
red staining. MDT-28 has been reported to be expressed in the proximal
germ line [52], suggesting an important role for MDT-28 in reproductive
tissues.