Year 1996 Awards
Minority Postdoctoral Research Fellowships
||Research Area/Training Plan
||NSF Award #|
|Title of Research and Training Plan|
|"The sperm components
required for sperm-oocyte interactions in C. elegans "
|The project uses several genes
that when mutated produce cytologically normal and motile sperm that cannot
fertilize oocytes even after contact. These mutations seem to disrupt
either sperm-oocyte recognition, adhesion, or fusion. Equivalent mutants
have not been described in any other metazoan. The approaches include
genetic, cell biological, and molecular biological ones to gain an understanding
of these genes and their mutant forms.
||University of Copenhagen
in embryological development"
|It is believed that the concentrations
of spatially distributed chemicals cause the patterned differentiation
of cells by causing differential responses in the genome. A mathematical
model of this hypothesis will be used to evaluate the capacity of such
a mechanism for suppression of the thermal fluctuations inherent in any
concentration, a necessary condition for the precision of embryological
||Indiana University, Bloomington
|"Duplicated DNA sequences
subjected to premeiotic methylation in a mushroom"
|The mushroom Coprinus cinereus
is used in this study because genes are normally present in only one copy
per nucleus, duplicated sequences are methylated premetotically in crosses,
and methylation effects are detectable in the veil cells of the mushroom
cap. This unique organism is ideally suited for studying premiotic homology
search in cell division. Genes have been isolated from the mushroom which
are necessary both for survival after gamma irridation and for meiosis.
These mutants are being used to study the role of MIP, methylation indued
premeiotically, in meiotic chromosome pairing and synapsis.
of population differentiation: comparative study of montane squamate species"
|The species under study are
five "sky island" reptiles from southern Arizona and New Mexico
that range in body size, dispersing ability, and habitat specificity.
The objective of the study is a detailed understanding of patterns of
genetic lineage differentiation under varying gene flow disruption regimes,
using naturally separated populations.
|| Eukaryotic Genetics
|"In vivo requirements
for appropriate expression of T-cell specific genes in mice"
|The locus control region (LCR)
sequences of specific T-cell receptor genes confer a high level of T-cell
specific expression of a linked transgene regardless of position in chromatin.
The structure and function of the LCR are being determined to shed light
on how the LCR exerts its powerful influence on gene expression.
||University of Arizona
|"Ecology of a complex
mutualism: measuring the costs and benefits of a well-known cactus-microorganism-Drosophila
|The principle mutualism in
the system under study appears to occur between Drosophila mojavensis
that feed and lay eggs on "rots" caused by various yeasts and
bacteria which parasitize host cacti, Stenocereus thurberi and Stenocereus
gummosus. The flies likely act as vectors of infection for the microorganisms.
It will be determined if the organisms provide each other with the hypothesized
||Amr. Museum Natural History
|"Origin of bioluminescence
in ostacode crustaceans: function and molecular evolution of luciferase
|Bioluminescence has evolved
independently numerous times in various organisms. Some luminescent cypridinid
ostracodes have a biochemically unique luciferase-lucferin system used
in courtship signaling but other species lack a light producing system.
These species provide a system to study the origin of the luciferase system,
hypothesized to be a mutation in an oxygenase.
|"How do chloroplasts
in the cytoplasm of plant cells communicate with the nucleus?"
|The proper development of plant
cells relies upon this communication. The mechanisms for this communication
are unclear even after many years of investigation and progress. There
is evidence that signals are relayed by the chloroplast and received by
the nucleus thus regulating specific genes. The project focuses on the
identity of these signals.
||Univ. Texas, SW Medical Center
|"The Isolation of MASH1
Expressing Cells from Transgenic Mice"
|The mammalian achaete-scute
homologous gene 1 (MASH1) is a neuron-specific transcription factor that
identifies neural precursors in multiple lineages at early stages of development
and, in some cases, is required for development to proceed. The aims are
to isolate, characterize, and compare MASH1 expressing precursors using
MASH1/lacZ expressing transgenic mice.
||University of California, San
Zebrafish Heart Tube Morphogenesis"
|Zebra fish will be used as
a model system to study early development of the vertebrate heart. A mutant
zebra fish which develops two hearts will be studied to determine how
many genes are involved and if they regulate cell migration and/or adhesion.
Using a variety of techniques of molecular biology, attempts will be made
to identify the genes involved in heart organogenesis.
||Harvard Medical School
||Intergrative Animal Biology
activity in cardiac development"
|The research and training plan
focuses on the development of the vertebrate heart using cells cultured
form chicken. A protein called ARIA known to stimulate the acetyl choline
receptor in the neuromuscular junction is also expressed during early
heart development This study seeks to determine the role of ARIA in early
heart development and to determine the developmental expression patterns
of its isoforms in this organ.
|"Genes regulating the
harsh touch response in the nematode Caenorhabditis elegans"
|Caenorhabditis elegans (C.
elegans, an important model for the study of developmental biology) responds
to harsh touch through 2 sensory neurons known as PVD. These neurons require
the homeobox domain protein MEC-3 for proper development of the touch
cells involved in the response. The genes involved in the harsh touch
response will be isolated taking advantage of their dependence on MEC-3
and the availability of mutants which lack the harsh touch response.
||University Maryland, College
of protein folding"
|The thermodynamic and kinetic
properties of in vitro and in vivo protein folding are being studied by
computational and analytical methods using lattice and off- lattice models.
The experimental problems being investigated involve protein design, chaperone
mediated folding, modeling of realistic protein structures such as for
cytochrome c and the analytical calculation of folding rates.
||University of Georgia
the MerR model"
|The mechanism by which a bacterium
survives exposure to the toxic metal mercury is being studied using the
Tn21 mercury resistance operon from a plasmid of the bacterium Shigella
flexeri. The study will determine how a regulatory protein, MerR, binds
to DNA and induces expression of a structural gene, merTPCAD, in response
to mercury exposure. It will be determined how MerR distinguishes between
mercury and other heavy metals also encountered in the environment. Mutants
whose MerR recognize cadmium and zinc will be generated and characterized.
Minority Graduate Student Travel
||Universidad de Granada, Spain
Minority Postdoctoral Research
Fellowship Third Year Extensions