Dr. Charles Walsh

Genetics
K. Arndt
T.-L. Ashman
G. Campbell
D. Chapman
G. Hatfull
J. Hildebrand
L. Jacobson
S. Kalisz
J. Martens
V. Oke
W. Saunders
B. Stronach
S. Tonsor
R. Wood

Microbiology
G. Hatfull
R. Hendrix
J. Lawrence
V. Oke
J. Pipas
M. Popa
I. Campbell
R.L. Duda
S. Godfrey

Molecular Biology
K. Arndt
J. Franzen
P. Grabowski
G. Hatfull
R. Hendrix
L. Jen-Jacobson
J. Martens
C. Peebles
J. Pipas
J. Rosenberg
A. Schwacha
C. Walsh

Plant Biology
T.-L. Ashman
W. Carson
S. Kalisz
V. Oke
C. Partanen
S. Tonsor
B. Traw

Science Education
A. Bledsoe
K. Curto
L. Daniels
S. Godfrey
N. Kaufmann
C. LaFave
J. Newman
E. Polinko
M. Popa
L. Roberts
T. Seiflein
R. Sherwin
A. Slinskey Legg

Structural Biology
M. Grabe
J. Hempel
R. Hendrix
L. Jen-Jacobson
J. Rosenberg
A. VanDemark

Former Faculty

Photo of Dr.
Walsh

Synthesis and Assembly of Eukaryotic Cellular Organelles

Associate Professor Emeritus

Dr. Walsh received his Ph.D. in 1968 from the University of California at Riverside and joined the Department in 1973.

Currently, Dr. Walsh is not accepting graduate students in his laboratory. Dr. Walsh is not accepting undergraduate researchers, and does not sponsor students in other laboratories.

Professional Interests - Publications - Contact Information - Lab Personnel

Professional Interests of Charles Walsh

Professor Walsh is interested in the molecular basis for cellular morphology. Much of his work in the past has focused on the regulation of the synthesis and assembly of eukaryotic flagella, basal bodies, and the microtubule cytoskeleton. More recently his laboratory has become interested in the molecular organization of the nucleolus.

Both areas of interest have been pursued by studying the differentiation of the amebo-flagellate Naegleria gruberi. Amebae of Naegleria are able to differentiate into swimming flagellates in a highly reproducible and synchronous fashion. During this process they are capable of the de novo synthesis and assembly of basal bodies as well as flagella and a microtubule cytoskeleton, all in less than two hours.

Nucleoli are known to be the sites of ribosomal RNA synthesis and ribosome assembly. The recent discovery in Dr. Walsh's laboratory of a system in which soluble components of the nucleolus can be reassembled in vitro has, for the first time, provided a way to examine the assembly of this important organelle. The fact that Naegleria have an exceptionally large nucleolus and the fact that all the ribosomal genes are present on about 4,000 copies of a small circular plasmid provide a rich context in which to explore questions of the molecular basis for the structure and function of nucleoli.

Professor Walsh's laboratory makes use of a combination of light microscopy (phase contrast, DIC, fluorescence, and confocal) and electron microscopy (transmission and scanning) using monoclonal antibodies to identify specific cellular components. Morphological data are combined with the results of cell fractionations and data from the cloning and sequencing of selected genes to try and provide an integrated picture of how cellular morphology determines and is determined by function.

Current projects involve the study of the in vitro reassembly of nucleolar proteins, DNA, and RNA; the organization and distribution of nucleolar proteins during mitosis in both Naegleria and in mammalian cells; and the synthesis and assembly of flagellar basal bodies.

Publication Archive
15 Citations
10 Abstracts
12 PDFs

Recent Publications of Charles Walsh

Kim, H.K., J.G. Kang, S. Yumura, C.J. Walsh, J.W. Cho, and J. Lee (2005) De novo formation of basal bodies in Naegleria gruberi: regulation by phosphorylation. J. Cell Biol. 169:719-724 (PDF Reprint: 597 kb)

Trimbur, G.M., J.L. Goeckeler, J.L. Brodsky, and C.J. Walsh (1999) Cloning, sequencing, and nucleolar targeting of the basal-body-binding protein BN46/51. J. Cell Sci. 112:1159-1168 (PDF Reprint: 356 kb)

Trimbur, G.M., and C.J. Walsh (1993) Nucleolus-like morphology produced during the in vitro reassociation of nucleolar components. J. Cell Biol. 122:753-766 (PDF Reprint: 7.2 MB)

Trimbur, G.M., and C.J. Walsh (1992) BN 46/51, a new nucleolar protein, binds to the basal body region in Naegleria gruberi flagellates. J. Cell Sci. 103:167-181 (PDF Reprint: 10.4 MB)

Lee, J.H., and C.J. Walsh (1988) Transcriptional regulation of coordinate changes in flagellar mRNAs during differentiation of Naegleria gruberi amebae into flagellates. Mol. Cell Biol. 8:2280-2287 (PDF Reprint: 1.9 MB)

Shea, D.K., and C. Walsh (1987) mRNAs for a- and b-tubulin and flagellar calmodulin are among those coordinately regulated when Naegleria gruberi amebae differentiate into flagellates. J. Cell Biol. 105:1303-1309 (PDF Reprint: 1.6 MB)

Mar, J., J.H. Lee, D. Shea, and C.J. Walsh (1986) New poly (A)+ RNAs appear coordinately during the differentiation of Naegleria gruberi amebae into flagellates. J. Cell Biol. 102:353-361 (PDF Reprint: 1.2 MB)

Walsh, C. (1984) Synthesis and assembly of the cytoskeleton of Naegleria gruberi flagellates. J. Cell Biol. 98:449-456 (PDF Reprint: 950 kb)

Walsh, C. (1980) Appearance of heat shock proteins during the induction of multiple flagella in Naegleria gruberi. J. Biol. Chem. 255:2629-2632 (PDF Reprint: 1.5 MB)

Fulton, C., and C. Walsh (1980) Cell differentiation and flagellar elongation in Naegleria gruberi. Dependence on transcription and translation. J. Cell Biol. 85:346-360 (PDF Reprint: 1.2 MB)

How to Contact Charles Walsh

US Mail
University of Pittsburgh
Department of Biological Sciences
213 Clapp Hall
4249 Fifth Avenue
Pittsburgh, PA 15260

Phone, FAX, Internet
Office : (412) 624-5025
Lab : (412) 624-4929
FAX : (412) 624-4759
Email : cwalsh+@pitt.edu
Web : http://www.pitt.edu/~cwalsh/

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