# MOLECULAR SIGNALING MECHANISMS IN EMBRYONIC INDUCTION

> **NIH NIH R01** · JOHNS HOPKINS UNIVERSITY · 1994 · $206,983

## Abstract

Chemical communication between cells plays a central role in guiding the
early development of vertebrate embryos. Such communication often involves
three molecularly distinct steps. First, ligands (such as peptide growth
factors) are released from transmitting cells. Second, information
concerning the binding of these ligands at surface receptors is transduced
across the plasma membrane and throughout the cytoplasm of receiving
cells. Third, this information is translated into differential gene
expression, thus achieving discrete patterns of cell determination and
differentiation in the embryo. The first and third steps in this process
have, thus far, received the most attention from developmental biologists.
Our long-term goal is to characterize the second step -- signal
transduction during embryogenesis -- at the same level of molecular detail
already achieved for these other steps. Success in this goal will
contribute significantly to our insight into the molecular mechanisms of
development, and thus define loci of both chemical teratogenesis and
inborn errors of development which give rise to birth defects.

The recent demonstration that the polyphosphoinositide (PI) cycle signal
transduction pathway plays an important role in embryonic mesoderm
induction provides us an unparalleled opportunity to begin achieving this
goal, as the PI cycle is arguably one of the best-understood signaling
pathways (in somatic cells). We propose to exploit this knowledge to
molecularly characterize this cycle's actions in mesoderm induction.
Specifically, the proposed studies will (1) employ novel spatially
resolved assays of PI cycle-mediated second messenger responses
(intracellular free Ca2+ changes and inositol 1,4,5-trisphosphate
production) to determine which (if any) putative mesoderm inducers
modulate embryonic PI cycle activity in a spatiotemporally dynamic manner;
(2) utilize well-established immunochemical and affinity chromatographic
techniques to identify the specific proteins involved (G proteins,
phospholipase C isozymes, plasma membrane receptors) and the molecular
mechanisms regulating their activities; and (3) bring to bear both
approaches in a strategy to detect and molecularly characterize as-yet
unidentified ligand receptors which may be involved in this aspect of
mesoderm induction.

## Key facts

- **NIH application ID:** 2198683
- **Project number:** 5R01HD022879-07
- **Recipient organization:** JOHNS HOPKINS UNIVERSITY
- **SAM.gov UEI:** FTMTDMBR29C7
- **Principal Investigator:** WILLIAM B BUSA
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 1994
- **Award amount:** $206,983
- **Award type:** 5
- **Project period:** 1987-05-01 → 1997-06-30

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/2198683

## Citation

> US National Institutes of Health, RePORTER application 2198683, MOLECULAR SIGNALING MECHANISMS IN EMBRYONIC INDUCTION (5R01HD022879-07). Retrieved via MORVS 2026-10-25 from https://api.morvs.ai/grant/nih/2198683. Licensed CC0.

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