Anthony Cashmore,
Ph. D.

Robert I. Williams Professor of Biology
Director, Plant Science Institute

103F Lynch Laboratories
Department of Biology
University of Pennsylvania
Philadelphia, PA 19104 USA

V	+1 215 898.9383
F	+1 215 898.8780
E	cashmore@sas.upenn.edu

photoregulatory signal regulation

My research interests concern the mechanism by which plants respond to light. Plants use several different photoreceptors to enable them to sense the quality and quantity of light in the surrounding environment. In response to this information they adjust their growth and development accordingly. We are interested in the nature of these photoreceptors and the signaling mechanisms utilized to initiate specific responses – such responses include (at the molecular level) membrane depolarization, synthesis of pigments, changes in gene expression (and at the developmental level) seed germination, stem elongation, and flowering.

Our studies involve the model plant Arabidopsis thaliana, and we utilize a combination of genetic, molecular, and biochemical approaches. Several years ago we characterized cryptochrome, a photoreceptor that selectively senses blue and UV-A light. Interest in this photoreceptor has recently been heightened by the finding that related cryptochrome photoreceptors are responsible for the entrainment of circadian rhythms in animals, including humans.

selected publications

Ahmad, M., Jarillo, J. A., Smirnova, O. and Cashmore, A. R. 1998. The cry1 blue light photoreceptor of Arabidopsis interacts with phytochrome A in vitro. Mol. Cell. 1: 939-948.

Ahmad, M., Jarillo, J. A., Smirnova, O. and Cashmore, A. R. 1998. Cryptochrome blue-light photoreceptors of Arabidopsis implicated in phototropism. Nature 392: 720-723.

Ahmad, M., Jarillo, J. and Cashmore, A. R. 1998. Chimeric proteins between cry1 and cry2 Arabidopsis blue light photoreceptors indicate overlapping functions and varying protein stability. Plant Cell 10: 197-207.

Cashmore, A. R. 1998. The cryptochrome family of blue/UV-A photoreceptors. J. Plant Res. 111: 267-270.

Cashmore, A. R. 1998. Higher-plant phytochrome: "I used to date histidine, but now I prefer serine". Proc. Natl. Acad. Sci. USA. 95: 13358-13360.

Jarillo, J. A. and Cashmore, A. R. 1998. Enlightenment of the COP1-HY5 complex in photomorphogenesis. Trends in Plant Science 3: 161-163.

Lin, C., Yang, H., Guo, H., Mockler, T., Chen, J. and Cashmore, A. R. 1998. Enhancement of the blue-light sensitivity of Arabidopsis seedlings by a blue light receptor cryptochrome 2. Proc. Natl. Acad. Sci. USA 95: 2686-2690.

Terzaghi, W. B., Bertekap, R. L. and Cashmore, A. R. 1997. Intracellular localization of GBF proteins and blue light-induced import of GBF2 fusion proteins into the nucleus of cultured Arabidopsis and soybean cells. Plant J. 11: 967-982.

Cashmore, A. R. 1997. The cryptochrome family of photoreceptors. Plant, Cell and Environ. 20: 764-767.

Ahmad, M. and Cashmore, A. R. 1997. The blue-light receptor cryptochrome 1 shows functional dependence on phytochrome A or phytochrome B in Arabidopsis thaliana. Plant J. 11: 421-427.

Ahmad, M., Jarillo, J. A., Klimczak, L. J., Landry, L. G., Peng, T., Last, R. L. and Cashmore, A. R. 1997. An enzyme similar to animal type II photolyases mediates photoreactivation in Arabidopsis thaliana. Plant Cell 9: 199-207.

Ahmad, M. and Cashmore, A. 1996. The pef mutants of Arabidopsis thaliana define lesions early in the phytochrome signaling pathway. Plant J. 10: 1103-1110.

Ahmad, M. and Cashmore, A. R. 1996. Seeing blue: the discovery of cryptochrome. Plant Mol. Biol. 30: 851-861.

Lin, C., Ahmad, M. and Cashmore, A. R. 1996. Arabidopsis cryptochrome 1 is a soluble protein mediating blue light-dependent regulation of plant growth and development. Plant J. 10: 893-902.

Lin, C., Ahmad, M., Chan, J. and Cashmore, A. R. 1996. CRY2: A second member of the Arabidopsis cryptochrome gene family. Plant Physiol. 110: 1047.