25, RUE DU DOCTEUR ROUX
       (XV' Arrond')

30 janvier

TM6phone i 566 - 58-00

Dr. Marshall W. NIRENBERG
Building 10 8D 13
Dept of Health,  Education & Welfare
Public Health Service
BETHESDA
Maryland 20014

Dear Marshall,

     I understand from the paper of Gordon Sato in
PNAS that you have developed a series of elegant micro-
assays for the enzymes of catecholamine, acetylcholine,
serotonin and GABA biosynthesis and catabolism.

       I have left the nematod v which do not allow me
to do what I would like,  I am turning now to work on mouse
nervous system and mouse cell cultures.   I have of course
no experience in the field, but I would very much like to
have in hand the techniques for the study of the trans-
mitters.  If you have no objection, I would be very
grateful for a detailed protocol for these enzyme and
transmitter assays.

    What is new with nematodaor with mouse neuro-
blastoma and other cells in your lab ?  Is there any
chance to see you around Paris in the near future ?
     With very best wishes,
                      Yours sincerely,

Franqois JACOB
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