|
Research Interests:
Prior to the 1950's, pregnancy in
eutherian mammals was thought to principally be controlled by the uterus, and
the fetus and the extraembryonic membranes that made up the placenta were merely passive participants
of pregnancy. However, in the 1960's this long-held belief was
challenged in several mammalian species, including cattle, sheep and other
ruminants. Classical embryo transfer studies completed by Drs. Moor
and Rowson demonstrated that the sheep and cow conceptus plays an active role in
dictating whether pregnancy will proceed past the length of a normal estrous
cycle. Through this work, it became apparent that the conceptus (fetus and
placenta) secretes a
factor during a critical period of pregnancy (day 12 of pregnancy in sheep and
day 16 of pregnancy in cattle) that extends pregnancy and prevents the return to
estrus. This is one aspect of what is now known as maternal recognition of
pregnancy. In the early 1980's, Drs. Roberts, Bazer and Thatcher working
at the University of Florida identified proteins produced by the sheep and cow
conceptus that were responsible for maternal recognition of pregnancy.
These proteins initially were termed ovine or bovine trophoblast protein-1
(oTP-1 or bTP-1), and since have been renamed as interferon-tau (IFN-τ)
when it was realized that these proteins were structurally and functionally
similar to Type I interferons.
The overarching goal of our research is to better understand the
physiological, endocrine, and molecular mechanisms that control early pregnancy in
cattle, sheep and other ruminant species (goat, deer, bison, giraffe). The
laboratory presently is focusing on three primary research endeavors:
1. The role of the
uterus in regulating conceptus development and IFN-τ
production.
It is clear that uterine secretory products are
required for optimal development of the conceptus during early pregnancy.
Recent evidence from our laboratory indicates that specific
uterine-derived factors regulate the production of IFN-τ. Our goal is to
identify these uterine-derived factors and understand how they affect
developmental and endocrine processes in the bovine conceptus.
Learn more about our lab's interest in
uterine-conceptus interactions:
2. The regulation of IFN-τ gene expression.
Expression of the IFN-τ gene (referred to as
ifnt) is regulated by a trophectoderm-specific promoter region, and thereby
is expressed specifically in the developing ruminant placenta. Elucidating
the molecular mechanisms that control ifnt expression are of particular
interest to the lab. Also, the lab is interested in using knowledge gained
from studying ifnt expression to better understand how other
placental-specific genes are regulated.
Learn more about our lab's interest in IFN-t gene expression.
3. Identifying schemes to reduce the incidence of
embryo mortality in cattle.
Early embryo mortality is prevalent among domestic
livestock, and failures in the establishment and maintenance of pregnancy are a
primary source of reproductive failures in cattle. The laboratory is
interested in transferring information gained from our endocrine and
molecular studies back to the animal in the hope that we will be able to limit
embryo mortality in cattle. Learn more
about our lab's interest in improving pregnancy rates in cattle.
| 