INTRODUCTION 
The accelerated growth of the research activities of 
the Institute that began in 1985 has been maintained 
through the present year and is projected to con- 
tinue in the coming year. As of August 31, 1989, 
there were 1,552 individuals engaged in the conduct 
of research and research administration at the 
Institute's units and associated laboratories. It is 
their research efforts that are reported in this vol- 
ume. The work was directed by 5 Senior Investiga- 
tors, 91 Investigators, 36 Associate Investigators, and 
60 Assistant Investigators and assisted by 49 Senior 
Associates and 424 postdoctoral Associates. The 
work of these scientists was aided by 449 research 
technicians, 94 research secretaries, and 344 others, 
including computer programmers, research special- 
ists, laboratory aides, and managers of administrative 
services with their associated office staffs. Also work- 
ing in the Institute's laboratories were 363 graduate 
students and 471 postdoctoral fellows, who contrib- 
uted to the research of the HHMI Investigators but 
were not employees of the Institute. 
LOCATIONS 
By the end of August 1989, laboratories of the 
Howard Hughes Medical Institute were located at 37 
sites in 30 cities in the United States, as listed else- 
where in this report. New or expanded research fa- 
cilities were completed at the University of Michigan, 
the University of Pennsylvania, and Stanford Univer- 
sity. Also under construction are laboratories at 
Children's Hospital in Boston, the University of Cali- 
fornia at Los Angeles and at San Diego, Yale Univer- 
sity and the University of Utah. 
The Institute continues to expand its support of 
selected individual investigators. A further 10 such 
investigators were added this year, bringing the total 
in this category to 25 and extending the Institute's 
activities to four new sites. Those appointed were As- 
sistant Investigators David J. Anderson, Ph.D., Pamela 
J. Bjorkman, Ph.D., and Paul W Sternberg, Ph.D., at 
the California Institute of Technology; Investigators 
John E. Donelson, Ph.D., and Michael J. Welsh, M.D., 
at the University of Iowa; Investigators Thomas E. 
Shenk, Ph.D., and Shirley M. Tilghman, Ph.D., at 
Princeton University; and Investigators Christopher 
Miller, Ph.D., and Michael Rosbash, Ph.D., at Bran- 
deis University. A second scientist, Associate Investi- 
gator Matthew P Scott, Ph.D., was appointed at the 
University of Colorado. Further appointments in this 
category will be made in the coming year, so as to ex- 
pand the Institute's presence at more institutions 
and to identify more promising new scientists at the 
Assistant Investigator level. 
INVESTIGATORS 
The following scientists were appointed to or pro- 
moted within the Institute's research staff: 
Investigators: 
Joan S. Brugge, Ph.D., University of Pennsylvania 
School of Medicine 
John E. Donelson, Ph.D., University of Iowa 
Uta Francke, M.D., Stanford University Medical 
Center 
H. Ronald Kaback, M.D., University of California, 
Los Angeles 
Susan L. Lindquist, Ph.D., The University of Chi- 
cago 
Christopher MiUer, Ph.D., Brandeis University 
Michael Rosbash, Ph.D., Brandeis University 
John W Sedat, Ph.D., University of California, San 
Francisco 
Thomas E. Shenk, Ph.D., Princeton University 
Paul B. Sigler, M.D., Ph.D., Yale University 
Shirley M. Tilghman, Ph.D., Princeton University 
Roger Y Tsien, Ph.D., University of California, San 
Diego 
Michael J. Welsh, M.D., University of Iowa 
Michael W Young, Ph.D., The Rockefeller Univer- 
sity 
Associate Investigators: 
David A. Agard, Ph.D., University of California, San 
Francisco 
Francis S. Collins, M.D., Ph.D., University of Michi- 
gan 
Elaine V Fuchs, Ph.D., The University of Chicago 
Randall R. Reed, Ph.D., The Johns Hopkins Univer- 
sity 
Matthew R Scott, Ph.D., University of Colorado 
Steven A. Siegelbaum, Ph.D., Columbia University 
Thomas C. Siidhof, M.D., University of Texas 
Southwestern Medical Center at Dallas 
Arthur Weiss, M.D., Ph.D., University of California, 
San Francisco 
Assistant Investigators: 
David J. Anderson, Ph.D., California Institute of 
Technology 
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