# BIOCHEM AND CLINICAL APPLICATION OF ACID PHOSPHATASE 5

> **NIH NIH R01** · UNIVERSITY OF TEXAS HLTH SCIENCE CENTER · 1987 · $111,424

## Abstract

This is a continuation of the previous study on the biochemistry and
clinical application of acid phosphatase 5 (AP5). The biochemical studies
will be directed toward constructing cDNA clones for AP5, verfication of
the authenticity of the putative cDNA for AP5, and determination of its
structure.  The positive cDNA clones will then be used to measure mRNA
levels in cells exhibiting different enzyme activities in order to
elucidate the regulatory mechanism of AP5 gene expression.  Experimentally,
partial amino acid sequence of AP5 will be determined and the information
will be used to synthesize oligonucleotide probes for screening cDNA clones
for AP5.  Total RNA will be extracted from hairy cells, which produce a
high level of the enzyme, using SDS -phenol or guanidine-HCL in the
presence of RNase inhibitors.  Poly A-containing RNA will be isolated using
oligo-dT cellulose affinity chromatography and the presence of mRNA for AP5
in the poly A-containing RNA fraction will be determined by in vitro
translation assay.  cDNA will be synthesized with reverse transcriptase and
cloned into pBR 322.  Plasmids harboring the isoenzyme 5 cDNA sequence will
be selected by hybridization with synthetic oligonucleotides containing
possible sequences coding for regions of the AP5 protein with a minimal
ambiguity in codon assignment, immunological screening with monospecific
anti isoenzyme 5 antibody and colorimetric method specific for AP5
activity.  Plasmid DNAs from the positive clones will be analyzed by gel
electrophoresis.  Clones containing the longest DNA inserts will be further
characterized by restriction endonuclease mapping and DNA sequencing.  The
amino acid sequence derived from the cDNA sequence will be compared with
that of AP5 to establish the authenticity of the cDNA clones.  AP5 mRNA
levels will be determined by Northern blot and dot-blot hybridization
experiments using the cloned isoenzyme 5 cDNAs.  To further decipher the
control mechanism of AP5 gene expression, longer term studies will include
isolation and characterization of genomic clones, using the characterized
cDNA clones, from the various cell types exhibiting different enzymatic
activities.  Positive genomic clones will be analyzed by restriction
endonuclese mapping, DNA methylation pattern analysis and DNA sequencing.

The continuation of the previous clinical study will include (a)
application of the DNA clones to elucidate the origin of hairy cells, and
(b) application of AP5 activity in the serum as a marker to follow the
therapeutic effectiveness in cancer patients, Gaucher patients and
Osteoporosis.

## Key facts

- **NIH application ID:** 3172703
- **Project number:** 5R01CA034881-05
- **Recipient organization:** UNIVERSITY OF TEXAS HLTH SCIENCE CENTER
- **SAM.gov UEI:** C3KXNLTAAY98
- **Principal Investigator:** KWOK-WAI LAM
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 1987
- **Award amount:** $111,424
- **Award type:** 5
- **Project period:** 1982-09-01 → 1989-01-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/3172703

## Citation

> US National Institutes of Health, RePORTER application 3172703, BIOCHEM AND CLINICAL APPLICATION OF ACID PHOSPHATASE 5 (5R01CA034881-05). Retrieved via MORVS 2026-10-25 from https://api.morvs.ai/grant/nih/3172703. Licensed CC0.

---

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