nology (Goldberg, A.M., Ed.). New York: M.A. 
Liebert, pp 55-61 . 
Articles 
Bohjanen, P.R., Petryniak, B., June, C.H., Thomp- 
son, C.B., and Lindsten, T. 1992. AU RNA-binding 
factors differ in their binding specificities and af- 
finities. /5/o/ Chem 267:6302-6309. 
Cooper, M.D., Chen, C.L., Bucy, R.P., and Thomp- 
son, C.B. 1991. Avian T cell ontogeny. Adv Im- 
munol 50:87-117 . 
Dayton, J. S., Turka, L.A., Thompson, C.B., and Mit- 
chell, B.S. 1991. Guanine ribonucleotide deple- 
tion inhibits T cell activation. Adv Exp Med Biol 
309B:293-296. 
Dayton, J.S., Turka, L.A., Thompson, C.B., and 
Mitchell, B.S. 1992. Comparison of the effects 
of mizoribine with those of azathioprine, 6- 
mercaptopurine, and mycophenolic acid on T 
lymphocyte proliferation and purine ribonucleo- 
tide metabolism. Mol Pharmacol 41:671-676. 
Lahti, J.M., Chen, C.L., Tjoelker, L.W., Pickel, J.M., 
Schat, K.A., Calnek, B.W., Thompson, C.B., and 
Cooper, M.D. 1991. Two distinct afi T-cell lin- 
eages can be distinguished by the differential 
usage of T-cell receptor V/3 gene segments. Proc 
Natl Acad Sci USA 88:10956-10960. 
McCormack, W.T., Tjoelker, L.W., Stella, G., Pos- 
tema, C.E., and Thompson, C.B. 1991 . Chicken 
T-cell receptor |8-chain diversity: an evolutionar- 
ily conserved D/3-encoded glycine turn within the 
hypervariable CDR3 domain. Proc Natl Acad Sci 
USA 88:7699-7703. 
Standiford, T.J., Lindsten, T., Thompson, C.B., 
Stricter, R.M., and Kunkel, S.L. 1992. Interleukin- 
4 differentially regulates tumor necrosis factor-a 
gene expression by human T lymphocytes and 
monocytes. Pathobiology 60:100-107. 
Takeda, S., Masteller, E.L., Thompson, C.B., and 
Buerstedde, J.-M. 1992. RAG-2 expression is not 
essential for chicken immunoglobulin gene con- 
version. Proc Natl Acad Sci USA 89:4023-4027. 
Thompson, C.B. 1992. RAG knockouts deliver a 
one/two punch. Curr Biol 2:180-182. 
Thompson, C.B., Wang, C.-Y., Ho, I.-C, Bohjanen, 
P R., Petryniak, B., June, C.H., Miesfeldt, S., 
Zhang, L., Nabel, G.J., Karpinski, B., and Lei- 
den, J.M. 1992. c/5-Acting sequences required 
for inducible interleukin-2 enhancer function 
bind a novel Ets-related protein, Elf-1. Mol Cell 
Biol 12:1043-1053. 
Turka, L.A., Kanner, S.B., Schieven, G.L., Thomp- 
son, C.B., and Ledbetter, J.A. 1992. CD45 modu- 
lates T cell receptor/CD3-induced activation of 
human thymocytes via regulation of tyrosine 
phosphorylation. Eur J Immunol 22:551-557. 
Turka, L.A., and Thompson, C.B. 1991. Structure- 
function relationship of immunosuppressive 
drugs: a cautionary tale. Hepatology 14:570- 
572. 
Vandenberghe, P., Freeman, G.J., Nadler, L.M., 
Fletcher, M.C., Kamoun, M., Turka, L.A., Ledbet- 
ter, J.A., Thompson, C.B., and June, C.H. 1992. 
Antibody and B7/BB1 -mediated ligation of the 
CD28 receptor induces tyrosine phosphorylation 
in human i: cells. J Exp Med 175:951-960. 
Wang, C.-Y., Petryniak, B., Ho, I.-C, Thompson, 
C.B., and Leiden, J.M. 1992. Evolutionarily con- 
served Ets family members display distinct DNA 
binding specificities. / Exp Med 175:1391- 
1399. 
MAMMALIAN MEMORY AND T LYMPHOCYTE FUNCTIONS 
SusuMu ToNEGAWA, Ph.D., Investigator 
Dr. Tonegawa's laboratory has had a long-standing 
interest in the development and functions of T lym- 
phocytes. While these immunological studies will 
actively continue, a new research interest, the mech- 
anism of mammalian learning and memory pro- 
cesses, has taken clear shape in the laboratory dur- 
ing the past year. 
Mammalian Memory 
As a first step in a program to use genetically al- 
tered mice to study learning and memory mecha- 
nisms. Dr. Tonegawa and his co-workers, using the 
embryonic stem (ES) cell gene-targeting technique, 
produced mutant mice that do not express the a-cal- 
cium/calmodulin-dependent kinase II (a-CaMKII), 
an enzyme highly enriched in postsynaptic densities 
of hippocampus and neocortex. The mice exhibit 
mostly normal behaviors, no obvious neuroana- 
tomical defects, and normal postsynaptic mecha- 
nisms, including 7V-methyl-D-aspartate (NMDA) re- 
ceptor function. However, they were shown to be 
deficient in long-term potentiation (LTP) in the hip- 
IMMUNOLOGY 363 
