بسم الله الرحمن
الرحيم. صلواة على سيدنا محمد وعلى آله وأصحابه أجمعين. و قل رب ادخلني مدخل صدق واخرجني
مخرج صدق واجعل لي من لدنك سلطانا نصيرا
محمد علي نقوي
Mohammad Ali
Naqvi
Phone # 647 300
1514
PROJECTS
Please click on
the title of a project for details
Vegetal Rotation in Xenopus laevis is an
important force generating process during Gastrulation that plays an important part
in tissue separation at the Brachet’s cleft, as well as in the internalization
of the mesoderm. XRhoA plays a major role in vegetal rotation since a
dominant-negative form thereof significantly blocks vegetal rotation.
Inhibiting Rho-Activated Kinase (ROK) also causes the same effect. The
blastopore never closes in these embryos. Here we show that the
DN-XRhoA-induced phenotype can be partially rescued by countering the effects
of the Dominant Negative with three times more amount of the Wildtype RNA. Moreover
we also found that inhibiting myosin just before vegetal rotation has a weak
effect on vegetal cell upwelling. This suggests the involvement of additional
players downstream of ROK in the pathway that causes vegetal cell upwelling
during gastrulation.
“The role of Rho-A GTPase in vegetal rotation (during
gastrulation) in Xenopus laevis ”
Vegetal Rotation in Xenopus laevis is an important force
generating process during Gastrulation that plays an important part in tissue
separation at the Brachet’s cleft, as well as in the internalization of the
mesoderm. Here we show that XRhoA plays a major role in vegetal rotation since
a dominant-negative form thereof significantly blocks vegetal rotation at low
and intermediate doses and freezes the embryos in the blastula stage at higher
doses with little or no development thereafter. The blastopore never closes in
these embryos. Moreover we also show that inhibition of ROK, a kinase acting downstream
of RhoA in many cell mobility pathways, produces a phenotype with respect to
vegetal rotation that is strikingly similar to the phenotype produced by
DN-XRhoA. This suggests a possible downstream role of ROK in RhoA signalling
during vegetal rotation.
“Does meiotic recombination vary with the genetic
determinants of fitness in an individual”?
This project investigated the
correlation between fitness and recombination (if any) in Drosophila
melanogaster. The idea that there might be such a correlation came from the
fact that adverse environmental conditions (such as a deviation from the
optimal temperature, overcrowding, malnutrition etc.) have long been known to
increase the rate of recombination. This increase in recombination, as
theorized, copes with the environmental stress by generating a unique haplotype
(in the next generation) that might carry the allelic combination perfectly
equipped to comply with the environmental stress.
These earlier investigations led to our
hypothesis that if an organism was subjected to stress by altering its genotype
rather than by changing the environment, it would also have a similar increase
in recombination as was observed with environmental stress in earlier studies.
In other words, individuals with a “bad” genotype should have a higher
recombination rate than those with “good” genotypes; because recombination in
case of a bad genotype may serve to assemble a better haplotype, whereas in
case of a good genotype, recombination may break apart an already good
haplotype.
Here we assumed that having deleterious
alleles would generate the same kind of effect on the overall physiology of the
organism as was caused due to environmental stress. For example a mutation that
debilitates the feeding apparatus will generate the same consequences as if the
individual was subjected to malnutrition or food shortage……...
Are
the mechanisms of Dorsal/Ventral axis specification, similar in all animals?
………. Perhaps, the difference
lies only in the location of the mouth!
Recently, the molecular components of
the BMP-Chordin system, that specifies the Dorsal/Ventral axis in Bilaterates,
have also been found and characterized in the Radiate Nematostella vectensis.
These morphogens, which are asymmetrically distributed in Bilaterates across
the presumptive dorsal/ventral axis (which they specify), are also found to be
asymmetrically distributed along an “invisible” directive axis in Nematostella.
Moreover, these molecules have also been proved to be similar to their
Bilaterate counterparts in sequence and function. This was revealed by studies
employing sequence homologies to construct phylogenetic trees, and to test the
effect of administering Radiate morphogens on developing vertebrate embryos…….
Non-coding RNAs and Gene Therapy
A significant number of diseases involve
a gain of function. This gain of function is either due to a mutant gene, or
due to loss of regulation of a gene. In addition, there are also diseases that
require a specific component of the cellular machinery to propagate. In all of
these cases, silencing a gene that is either itself responsible for the disease
or is involved in its propagation, can serve to alleviate the disease symptoms.
RNA interference is a naturally occurring phenomenon that the cells employ in
order to regulate gene expression during development as well as in routine
metabolism. This mechanism involves the use of anti-sense RNA to recognize the
target mRNA, which is subsequently degraded. Recently, researchers developed
gene-silencing approaches based on RNA interference by designing synthetic
small interfering RNAs (siRNA), as well as DNA constructs that get transcribed
to short hairpin RNAs (shRNA) in the cell. The shRNAs are in turn processed by
cellular enzymes to siRNAs. RNA interference through shRNAs has proved to be an
effective and long term silencing mechanism that can potentially be applied to
many human disorders ranging from cancer and prion diseases to the diseases
caused by viruses such as HIV & HPV…………….
Osprey fact sheet (2003, while
working for TRCA)
The osprey is a large bird of prey about
the size of a small eagle. The crown and upper nape are white, streaked with dark
brown. The crown also bears a crest, which is not erectile but rides in the
wind as the bird flies. The dorsal aspect of the bird's body is chocolate
colored from the lower portion of nape, through the mantle, back, wings and
rump, down to the tip of the tail. In contrast, the chin, throat, breast,
belly, flanks, shins, undertail coverts, lesser underwing coverts and vent
feathers are primarily white with sparse mottling, which is more pronounced in
females than the males; males tend to be whiter on the underside than
females……….
Two other fact sheets on artificial Hibernaculum for Snakes at Snell grove Conservation Area