Hemorandum program of research with Prefessor =. L. Tatum at Stanford
University -- February-HMarch-acril 1956

Genetics of Neurospora fragnents

Preliminary note. Ae is vrobably familicr to you, 1 worked for ay ©h.D. with
Profescor Tatum «t Yale University in 1946-47. Frier to that time I had worked
on Neurospora with Ryan «% Columbia. While Tatum hee continued Beuroepera
studies, we have concentrated on becteria, but hope to ure the axperienee ace
cumulated in the bacteriel work for 4 renewed attack on some rroblems for which
Nearospora may be the best experiments] manatertial.

Zrogram. It ie not certain thet all of the following lines will be followed,
devending on the succesa of more preliminary work. However, se at least thre:
peeple will be concentrating on the rrogram, with the pessible assistance of
etill others, it should be feasible to do at leset the groundwork for moet of
the following.

i. Viability and fertility of hyphal fragments. ‘@atum had noted thet after
Veurespore myceliun ie diarupted in a Waring blender, freetions can be separe ted
whore rarticles gen: too wmzll te be bites of hyphae, bat still retain the abils ty
te function in semi] fertilisation. The fragnents ealeo retein sone vagetative
viability. It fe preposed that these fraguents uay be, in effect, neariy neked
nuglel, which nesde te be tested by more direct microseepic control and cheni-
@el and physicel analysis.

2. Before undertaking sintliar work with bacteris, in 1946 Ryan end I had
attenpted to transduce genetic markers to Neurosvora hy neang of WA-~containing
extracts. It in proposed te rerest such experiuents, by treating the fragments,
in the hove that these will be more permeable te necronolacnlar materials, The

fragments will be tested as well fer unusual guséeptibility te other trentmente
(especieliy chemical mutagens and DiA-nase) that can be expseted te affect
their genetic content. Various other means of achieving transdnetion, 6.4,
by limited ultragenic diaruption of heterskeryetic mreelia, will also be
atteupted,

Je An abtenpt will be made to dewelop « techniaue for direct intra-hyphal
implantation, by means of nieropipettes, ef nuclei, cytoplasm and other frac-
tions. This hax an obvious bearing on the problems above, and aleo on the
study of extranuclenr hereditary factore (26 in the eytevleanic *reky" muta~

tien in Hewrespora),

In principle, any of this werk eould be done here, bet I would not ore~-
pose to do ao. The advantages of Stanford are firstly, of course, Dr. Tatunts
aotive collaboration, and his wealth of experience with the materinis. In
addition, there is svailable there on unemumled eollegtion ef stecke accear
to which would be avkward at a distanee. Finally there is 2 laberstory ond
pereonnel getup there already orennized fer thie type of work on Feurorcere,
to duplieste which, for thene exrloratery etudias, would enteil » grent deal
of time and effort. It is hoped that thene explotations can be substantially
completed in three months; if not, the further division of laber between the
two laboratories will have te be vorked out,

Subs tthed hy:

Frofersor J. Laderberg