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implying that these associations maybe worm, to identify novel factors. One such novel
protecting the cell from the toxic effects of CAG factor, induced strongly in the regenerating
repeat RNA. Besides SCA17, we found that worm, was christened Neev. Neev was
Stat1, a key regulator of interferon pathway expressed in four dots per segment, at the base
genes was induced in mouse models of other of each chaetae, the chitin coated projections
polyglutamine diseases. We are currently that allow the worm to grip and move through
exploring if the induction of interferon pathway soil. In the regenerating worm, the expression
is a common feature of multiple polyglutamine of Neev was highest in regions where new
disease models. Further, tools for knocking chaetae were being formed. Sequence analysis
down interferon expression have been showed that it has minimal protein coding
developed. The potential protective role of potential, suggesting this was a non-coding
knockdown of interferon signaling in the mouse RNA. The sequence of Neev presented several
brain will be explored in future. binding sites for miRNAs, which were also
complementary to the Chitin synthase 8 gene.
Novel Regeneration Factors from Earthworm We reasoned that Chitin synthase maybe
Neurons are highly polarized with specialized induced in only those cells that form the base of
sub-cellular locations that make contacts with the chaetae, and only during the formation of
other neurons. In the adult mammalian central new chaetae. The lncRNA Neev, we proposed,
nervous system, most neurons are terminally sponges away miRNAs and allows the selective
differentiated and barring a limited supply of derepression of chitin synthase in the
stem cells, there is little regenerative potential. regenerating tissue. LncRNAs that act as miRNA
In sharp contrast, several invertebrates can sponges can be expressed in a highly restricted
regenerate nerves following amputation. We pattern, ensuring spatio-temporal regulation
initiated work on the earthworm, Eisenia fetida during regeneration.
to identify novel regeneration factors that may
be responsible for the remarkable regenerative Besides these major projects, a method for
potential of this worm. This six-inch long, top- miRNA profiling in patient serum was developed
soil dwelling, vermicomposting worm, when cut and deployed to study the differences between
into two pieces, will regenerate the muscle, gut, mild/ moderate and severe patients. This
nerve cord and vasculature in the posterior method was also used for biomarker
region. We carried out genome sequencing, identification in Downs syndrome patients
time dependent transcriptome analysis and classified according to the severity of neuro-
metagenome analysis of the regenerating developmental defects.
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