Research Interests  
Gastrulation is the developmental process through which metazoan embryos establish and organize the three germ layers of the mature organism. Though there are several conserved aspects to the system of cellular movements and molecular players that multicellular animals use to gastrulate, the timing, deployment, and use of these elements varies widely between species.

I am interested in studying the process of gastrulation in Parhyale hawaiensis to contribute to the growing body of knowledge regarding gastrulation strategies in non-model organisms. In P. hawaiensis, gastrulation begins with internalization of the small group of mesoderm and germline precursor cells that make up a structure called the rosette.  This part of gastrulation finishes with the rosette beneath another population of cells, an ectodermal cell sheet. We are interested in determining which population of cells actively migrates and in defining the mechanistic and molecular pathways that initiate and regulate this migration. Previous studies point to gastrulation as a critical time in fate determination during P. hawaiensis development (1), but little is understood about its mechanistic and molecular aspects. Preliminary cell-labeling and time-lapse video of each population of cells suggests an active role on the part of both the ectoderm and the rosette (2,3).  Molecularly, prospective mesoderm markers such as the P. hawaiensis homologs of the Drosophila genes snail and twist are not expressed until after gastrulation is finished (4).  The late expression of these genes indicates that new molecular markers must be isolated in order to differentiate and possibly manipulate the rosette and ectoderm during gastrulation.  To study Parhyale gastrulation in further deatil, I propose to carry out several experiments including a detailed description of rosette internalization using high-magnification time-lapse with in-vivo labeling techniques and histology, expression and manipulation studies of conserved genes involved in cell migration, and small molecule inhibition of signaling pathways.

References:

1.Price AL, Modrell M, and Patel NH (2008). Manuscript in prep. 2. Browne W, et al. (2005) Genesis 42(3): 124-1483. 3. Price AL. (2005). Dissertation. 4. Price AL and Patel NH (2006). J Exp Zool (Mol Dev Evol).

Education
PhD student, University of California, Berkeley
Department of Integrative Biology
Dr. Nipam H. Patel, advisor
August 2006– present

B.A., Biology, Reed College, Portland OR
Thesis: "Gastrulation and Inversion, Morphogenetic Movements during Spider Development,"
Dr. Steven D. Black, advisor
August 1998 - December 2002

Teaching Experience
Graduate Student Instructor, General Biology, UC Berkeley, 2007–present
Teaching Assistant, Arthropod Module, Wood’s Hole Embryology Course, summer 2007

Publications
Chaw R., Vance, E. and Black, S. (2007) Gastrulation occurs in three phases during the development of the spider Zygiella x-notata. Developmental Dynamics 236: 3484-3495.

Chaw R. and Black, S. (2008). Mechanisms of inversion in spider development.  Manuscript in prep.

Presentations
"Gastrulation and Inversion in Spider Embryos" (poster)
Northwest Developmental Biology Conference, Friday Harbor WA
Received outstanding poster award, First Place, 2003

"Gastrulation and Inversion in Spider Development"
American Arachnological Society Annual Meeting, Denver CO
Received outstanding research talk, Second Place, 2003

Fellowships, Grants, and Awards
NSF Graduate Research Fellowship, 2006
Mellon Fellowship, Reed College, 2005–2006
Phi Beta Kappa, Reed College
Class of '21 Award, Most innovative thesis, Reed College