# STRUCTURAL AND CHEMICAL STUDY OF TISSUE CALCIFICATION

> **NIH NIH R01** · UNIVERSITY OF TEXAS HLTH SCI CTR HOUSTON · 1988 · $94,238

## Abstract

The overall goal of this research is:  (1) to identify intermediate
calcium carriers which have a common mineralizing function in
distantly related organisms, (2) to determine whether or not the
carriers are derived from a common ancestral gene (3) to
characterize the mineral-binding domains of the intermediate
carriers, and (4) to determine how carrier-bound calcium ions are
utilized to form a crystalline mineral phase.

The specific aims for this proposal are:  I.  To demonstrate that
phosphophoryn sequesters calcium phosphate in protected
domains which are stable in the extracellular environment.  II.
To demonstrate that the bivalve hemocytes produce large
quantities of native phosphoprotein particles.  III.  To isolate and
characterize the coccolithisomes from the unicellular alga
Hymenomonas carterae.  IV.  To determine the primary structure
of phosphoprotein particles and identify any sequences
homologous to the dentin phosphoprotein.  Phosphophoryn,
phosphoprotein particles, and coccolithisomes are the high-
capacity calcium carriers in vertebrate dentin, molluscan
bivalves, and unicellular algae, respectively.

Ligand-binding studies are used to characterize the calcium
phosphate sequestering domains in phosphophoryn.  Cellular
synthesis of native phosphoprotein particles is examined by
immunocytochemistry and in vivo and in vitro translation of
mRNA.  Coccolithisomes are isolated by subcellular
fractionation and ion exchange, molecular sieve, and affinity
chromatography.  Then the algal calcium carriers are
characterized by amino acid and carbohydrate analysis.  The
primary structure of the phosphoprotein particles is determined
from the nucleotide sequence of the cDNA.

This project examines universal mineralization mechanisms
applicable to normal skeletal and pathological calcification
processes.

## Key facts

- **NIH application ID:** 3157498
- **Project number:** 5R01AR036239-05
- **Recipient organization:** UNIVERSITY OF TEXAS HLTH SCI CTR HOUSTON
- **SAM.gov UEI:** ZUFBNVZ587D4
- **Principal Investigator:** MARY E MARSH
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 1988
- **Award amount:** $94,238
- **Award type:** 5
- **Project period:** 1985-01-01 → 1990-06-30

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/3157498

## Citation

> US National Institutes of Health, RePORTER application 3157498, STRUCTURAL AND CHEMICAL STUDY OF TISSUE CALCIFICATION (5R01AR036239-05). Retrieved via MORVS 2026-10-25 from https://api.morvs.ai/grant/nih/3157498. Licensed CC0.

---

*[NIH grants dataset](/datasets/nih-grants) · CC0 1.0*