BIOCHEMICAL

Vol. 76, No. 2, 1977

AND BIOPHYSICAL

RESEARCH COMMUNICATIONS

CORRECT ION THE BrOSYNTHESIS

OF PHOSPHORYLATED TYROSINE HYDROXYLASE BY ORGAN CULTURES OF

RAT ADRENAL MEDULLA AND SUPERIOR CERVICAL GANGLIA: A CORRECTION

Carol

Section

H. Letendre,

on Intermediary

of Child

Health

Maryland

Paul

Metabolism,

Behavioral

and Human Development,

inorganic

paper

phosphate

(1)

is

Biology

National

tissues.

rat

England

Nuclear

Guroff

Branch,

Institutes

between

10 and 15% of the

their

into

"P

National

Institute

of Health,

Nuclear,

phosphorylation.

Indeed,

appears

from our This

earlier

accuracy.

of enzyme.

paper,

correction Second,

it

Bethesda,

phosphorylation

On the other

in the steady These hand,

the

event,

experiments, if

with state

with

under specific

population

basis

would

that conditions.

levels

of

is

we reprint

for

hydroxylase

the

Table

then

scientific If the

to consider

existing

in two

make sense

to do

CAMP, reserpine, of phosphorylated

contains

simple

of the work.

seem logical

have not

each enzyme molecule

by New

activities

higher

First,

It would

exogenous

our

of

figures.

tyrosine

incidentally,

Copyright 0 1977 by Academic Press, Inc. All rights of reproduction in any form reserved.

correct

it

provided

one mole of phosphate

the conceptual lo-15%

cultures

us to conclude

revised

on two counts.

in fact,

led

sake of correction

and nonphosphorylated.

as we have done,

some alteration molecules.

is,

information

substantially

almost

For the

seems to change

a regulatory

phosphorylated

experiments,

indicates

now containing

of phosphorylation

upon

radioactive

in organ

phosphorylated

based

seems appropriate it

upon the

were

that

that

hydroxylase

monophosphate,

calculations,

by New England

per mole

based

potassium

now furnished

showing

tyrosine

enzyme molecules

of these

incorporated

experiments

Our calculations,

about

A reconsideration

we presented

incorporated

certain

forms,

and Gordon

20014

In a recent

level

C. MacDonnell

etc.,

to look

for

and nonphosphorylated

revealed

such an alteration.

one molecule

of phosphate,

as it

615 ISSN

0006-291X

that

6.15

Nerve growth factor-treated

on the assumption

3.05

*based

32

and without

pretreatment

leucine

comprises

0.492

0.266

10% of the

pmol/SCG

with

pmol/SCG

rats

monophosphate

P-Phosphate incorporation into tyrosine hydroxylase

3

old

and 32 P-potassium

H-Leucine incorporation into tyrosine hydroxylase

of 5-day

of 3H-L-leucine

Control

Treatment

ganglia

Incorporation

TABLE I

tyrosine

hydroxylase

79

87

%

Phosphorylation*

animals

tyrosine

of the

into with

growth

factor.

of superior

molecule

5735

5417

pmol/SCG

32P-Phosphate incorporation into acid-insoluble material

nerve

hydroxylase

cervical

"0

H

i=

z F r iTI v)

8

z

5 F

3

.-5 .? if J

BIOCHEMICAL

Vol. 76, No. 2, 1977

now seems, phosphate

such experiments as a constitutive

regulatory

phenomena.

calculations the action

1.

of tyrosine

Letendre, 74,

less

part

of

We are

and experience.

enzyme and not

are

one whose

attractive,

addition

and it

is

possible

to think

to this is,

latter

we now consider and removal

plays

view,

based

phosphate

of the

in any meaningfu

the enzyme and not a participant

inclined That

AND BIOPHYSICAL RESEARCH COMMUNICATIONS

on our

recent

a normal

part

a regulatory

role

of

in the

hydroxylase.

C. H.,

P. C. MacDonnell,

and G. Guroff,

891 (1977).

617

Biochem.

Biophys.

Res. Comm.