ANNUAL REPORT - Department of Biotechnology

primers (Operon) under the series OPAA (OPAA1-
20) and OPL (1-10) were screened for amplification
by polymerase chain reaction. Five strains isolated
from various parts of Kerala have been characterized
by RAPD with 20 primers. Bioassay has been carried
out with 58 isolates and 13 reference strains on
larvae of the insect Diaphania indica, which is
emerging as a problem for the cultivation of
vegetables in Kerala. TNAU, Coimbatore collected
soil samples from 759 different spots of fourteen
different divisions of the Western Ghats forests in
Tamil Nadu and out of 392 soil samples tested from
various sites of Western Ghats, 285 samples were
found positive for presence of B. thuringiensis
isolates. From 285 soil samples, 343 new isolates of
B. thuringiensis were identified based on the
presence of crystalline inclusions. Forty nine of the
new isolates of Bt were screened for toxicity against
neonate larvae of Helicoverpa armigera and four of
the new isolates were found to be on par with the
reference strain, HD1 for toxicity against Helicoverpa
armigera.
Plant Molecular Biology Programmes :
Research projects related to plant molecular biology
are being supported at the following four
universities/institutions: -
University of Delhi, South Campus New Delhi:
The CPMB at South Campus has four inter-related
sub-areas of activity in the general area of plant
molecular biology. The progress of work on these
aspects is given as follows; analysis of inflorescence
specific promoters from rice has revealed temporal
pattern of gene expression under control of four
promoters investigated. In case of OSIPP2, gus
expression was evident after meiosis when
microspores were released from callose wall and
could be seen even after germination of pollen grains.
Deletion constructs of promoters from OSIPK and
OSIPA showed variable activity in Arabidopsis.
Functional validation of OSISAP2 and OSIRPK
revealed their activity in stress response and
transgenics over-expressing these genes show
stress tolerance. Performance of OSIRPK was better
than OSISAP2. Stress tolerant rice with codA genes
were investigated for mechanistic aspects in terms of
transcription activity. Out of 31 AUX/IAA gene in rice,
DBT Annual Report 2006-07
40
OSIAA4 lacks a critical domain II which is known to
be responsible for proteasome-mediated
degradation, a prerequisite for auxin-induceed
responses. Cryptochromes(CRY) are blue/UV-A
light sensing photoreceptors involved in regulating
various growth and developmental responses in
plants. The group has functionally validated BnCRY1
gene from Brassica napus, an oilseed crop, by
regulating its expression in B. juncea transgenics. In
contrast, the transgenics over-expressing CRY1
were distinctly short and accumulated anthocyanins
at a higher level. These data provide functional
evidence for a role of blue light up-regulated cry1 in
controlling photomorphogenesis in Brassica
species.
The protocol for induction of somatic embryogenesis
has been used to create a cDNA library of wheat
(Triticum aestivum CPAN1676) for the isolation of
early auxin inducible genes. For screening the
library differentially, reverse northern for nearly 1500
clones were carried out using cDNA population
derived from mRNA (isolated form the total RNA) of
auxin treated and control samples. Database
searches revealed the recovery of many previously
known plant somatic embryogenesis (SE)-related
genes, while the work on some of these novel genes
is in progress, we have identified at least 15 ESTs
from wheat (Triticum aestivum), which exhibit high
sequence identity with Aux/IAA homologs in other
species. One of these Aux/IAA genes, TaIAA1, has
been characterized and encodes a nuclear localized
protein, harboring all the four conserved domains
characteristic of the Aux/IAA proteins. The
expression of TaIAA1 is light-sensitive, tissuespecific.
Isolation and characterization of abiotic
stress-induced promoters is the need of the hour.
Nearly 2 kb long rice hsp100 promoter was cloned
upstream to gus reporter gene in pCAMBIA vector
and the construct was transformed into rice. Putative
transgenics have been analyzed for integrity and
expression of the transgene by PCR, northern
expression and for histochemical and fluorometric
GUS expression. This analysis has suggested that
hsp100 promoter is regulated by high temperature
stress. Apart from high temperature, specific metals
(such as arsenite and cadmium) also induced rice
hsp100 promoter. This promoter has one distinct
heat shock element. Experiments are underway to
determine the functional role(s) of this element as