Dan Lindsley Symposium, UC/San Diego, October 14-15, 1990

What is biological evidence? Summary.   SLIDE
Cairns, Mittler & Lenski
B. Hall

DIFFERENTIAL MUTATIONS on induction
In fact there is a handful of simple but persuasive examples,
at least back to 1973
BROCK  1971    SLIDE
??Does Lac induction enhance DES penetration?
muta action?
generally
(other loci not examined)

No effect of IPTG on spontaneous rate
Kohno & Roth. I.D. Laci: proflavine
Herman & Dworkin 1971  similar

Differential Repair
ongoing work from Hanawalt lab.
Cockayne syndrome, Venema lab

Reed & Hutchinson
other attr. to replication fork

INSERTIONAL MUTAGENESIS
Lodge & Berg
J Bact 10/90
Tn5 tet transcription
Isberg & Syvanan 1982
DNA gyrase needed for Tn5
topo I mutation
Pelement - M. Young
Retrovirus integration
numerous reports
Jaevisch reviewed Scherdin
from SD state
Michael Breindl
mouse fibroblast & germ line
1. active genes are targetted
2. insertions near regulatory
DNAse-1 hypersensitive
therefore lethals

SS-DNA (other non B) DNA in vitro
deamination of cytosines SS 140 x ds
200 yrs vs
30,000     SLIDE

many other mutagens
e.g. chloroacetaldehyde

On other hand   SS-06-MeDNA is not repaired
by the suicide substrate Me transferese pathway (Lindahl)
mutations stick

Hot Spots
many kinds
CPG (related to methylation)
at least in euk.-->transcr control
poly (CG) deletions   FUCHS
related to ZDNA
Wells: transcription facilitates Z transition

Footprint reagents
DNAse 1
Uranyl                protein binding
psoralen
DMS

KMn04     Z
OSO4       or
DEPC       SSDNA

Site specific
-ases
epigenetic
B subtilis
Ananaboena
ph variation
immunogenesis  Yokota 12/89
  brain DNA

DNA - amplif
Mekalanos
Roth - growth
assumed selective
Pesticide?    induced
DNA amplif
Soreq...
Culex?
Tr - recomb
yeast      SLIDE
gyrase
Nal R - gyr A mutants
resists. EthDr relaxation
?full methylation?
MNNG res.
not to MMS
       EMS
presume mostly relaxed
overproduction of groEL

Wrapup     SLIDE

Exp paradigm      SLIDE

* Disadvantage, have only just returned to the lab and no new
  experiments yet.  Glad to anticipate in advance acknowledgments
  to David Thaler and Ken Zahn, who've just joined me.

To talk about genuine plasticity is something of a new departure for me.

SO WHAT      long shot - hunt for genes this way
DRAKE
BIBL
THANKS TO ORGANIZERS