# MECHANISM OF SEGREGATION OF MODIFIED TUBULIN IN VIVO

> **NIH NIH R01** · UNIVERSITY OF CALIFORNIA LOS ANGELES · 1987 · $68,039

## Abstract

The long-range goal of this research is to understand the purpose and
mechanism of a cytoskeletal differentiation, that is, modifications in the
cytoskeleton which alter its role in cellular events.  In particular, a
reversible post-translational modification of a tubulin involves the
addition or removal of a tyrosine residue at the C terminus.  Previous
research in the laboratory has determined that tyrosinated and
nontyrosinated tubulin are contained in different populations of
macrotubules in cultured cells.  The aims of this project are three-fold:
(1) to determine whether asymmetry of distribution of nontyrosinated (Glu)
and tyrosinated (Tyr) tubulins in microtubules is of widespread occurrence;
(2)\to ascertain whether or not the segregation of the Glu and Tyr tubulins
into separate microtubules appears to be involved in mitosis or cell
transformation; and (3) to determine the mechanism by which these two
post-translationally modified tubulins become differentially distributed in
vivo.  Several types of cultured cells will be examined using peptide
antibodies specific for Tyr and for Glu tubulin.  Cells engaged in mitosis
will be examined with light and electron microscopic immunolocalization in
order to determine which population of mitotic microtubules contain which
species of alpha-tubulin.  Transformation by SV40 virus in two cell lines
will be used as an example of cytoskeletal abnormalities induced by
transformation.  In each case in which asymmetry of Tyr and Glu tubulin is
observed, the location and any putative functions of microtubules
containing each will be noted.  To learn about the significance and the
mechanism of obtaining the  observed differential distribution of Tyr and
Glu tubulin, microtubules will be depolymerized in vivo and in lysed cell
models.  Repolymerization under several conditions will result in
differential or equivalent distributions of Glu and Tyr tubulin.  Several
possible mechanisms for the segregation of Glu and Tyr tubulins into
separate microtubules can thus be tested.

Since the abnormal function of microtubules is an integral part of cancer
and other diseases, attempts to discover the control of their localization
and function in cell division, differentiation, and transformation is of
obvious importance.  (L)

## Key facts

- **NIH application ID:** 3179158
- **Project number:** 5R01CA039755-03
- **Recipient organization:** UNIVERSITY OF CALIFORNIA LOS ANGELES
- **SAM.gov UEI:** RN64EPNH8JC6
- **Principal Investigator:** JEANNETTE CHLOE BULINSKI
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 1987
- **Award amount:** $68,039
- **Award type:** 5
- **Project period:** 1985-04-01 → 1988-03-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/3179158

## Citation

> US National Institutes of Health, RePORTER application 3179158, MECHANISM OF SEGREGATION OF MODIFIED TUBULIN IN VIVO (5R01CA039755-03). Retrieved via MORVS 2026-10-25 from https://api.morvs.ai/grant/nih/3179158. Licensed CC0.

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