Carmen Catala
Adjunct Scientist
Office/Lab: Room 315/316
Contact: cc283@cornell.edu/ / 607-254-4560
Affiliations:
Senior Research Associate Department of Plant Biology Cornell University
Graduate Field: Plant Biology, Plant Pathology
Research Summary
My research program is centered on developing a comprehensive understanding of auxin homeostasis and signaling, primarily using tomato fruit development as a model experimental system.
The plant hormone auxin controls many aspects of growth and development and plays a central role in coordinating cell division, expansion and differentiation. However, despite major advances in elucidating many aspects of auxin metabolism, transport and signaling in vegetative tissues, the nature and importance of these processes in fruit development and ripening is unknown. Within the general goal of understanding how auxin regulates fruit development, we seek to answer two major questions: (1) How does auxin control cell wall modification during rapid cell expansion; and (2) What determines auxin concentration and distribution in developing fruit.
The nature of auxin-regulated signaling networks for cell wall modification
Wall restructuring plays an essential role in many auxin-regulated processes and rapid cell wall loosening mediated by auxin is a well-studied phenomenon. Recent breakthroughs in the field of auxin signaling allow the auxin signal to be tracked from its interaction with a receptor to changes in gene transcription, through a proteasome-mediated protein degradation pathway. However nothing is yet known about how this pathway is linked to the downstream effects of auxin at the cell wall level.
The goal of this research is to identify components of the auxin signaling pathway controlling downstream effectors of cell wall remodeling that are necessary for the growth response. The experimental approaches being taken include analyses of the transcriptional control of auxin-response genes encoding cell wall modifying proteins, such as expansins. In addition, since some of the rapid responses to auxin may not involve gene transcription we are using proteomics techniques to investigate apoplastic events involved in the early, rapid, auxin-induced wall loosening. For example, we are using iTRAQ based comparative proteomics for the large scale profiling and quantification of protein expression.
This research will not only shed light on the pathways leading to wall modification during fruit growth and development, but also will expand to related important areas, such as the mechanisms controlling overall plant growth and cell wall properties.
The mechanisms by which auxin is produced, transported and metabolized in tomato fruit through development and how these mechanisms control auxin levels and associated signaling
The distinct phases of tomato fruit development constitute an excellent system to study the complex interplay between synthesis, conjugation and transport of auxin, and classical physiological studies have long suggested that auxin plays a regulatory role in different stages of fruit ontogeny. We are interested in addressing the following questions: How and where is auxin produced, and what are the main mechanisms of auxin metabolism in the developing tomato fruit? What are the mechanisms of transport of auxin in the developing fruit and how is polar auxin transport involved? A central component of my research program involves the application of advanced and sensitive analytical techniques to monitor the levels of auxin and related metabolites, and genes involved in auxin metabolism, transport and signaling. The information provided by these approaches will be integrated to offer a clearer picture of the role of auxin in the control of fruit development.
Publications
Urbanowicz, B.R., Catalá, C., Irwin, D., Wilson, D.B., Ripoll, D.R. and Rose, J.K.C. 2007. A Tomato Endo-Β-1,4-glucanase, SlCel9C1, Represents a Distinct Subclass with a New Family of Carbohydrate Binding Modules (CBM49). J. Biol. Chem 282: 12066-12074
Isaacson, T., Damasceno, C.M.B., Saravanan, R.S., He, Y., Catalá, C., Saladié, M. and Rose, J.K.C.. 2006. Sample extraction techniques for enhanced proteomic analysis of plant tissues.. Nature Protocols 1: 769 -774
Saladié, M., Rose, J.K.C., Cosgrove, D.J. and Catalá, C.. 2006. Characterization of a new xyloglucan endotransglucosylase/hydrolase (XTH) from ripening tomato fruit and implications for the diverse modes of enzymic action. Plant J 47: 282-295
Rose J.K.C., Saladié, M., Catalá, C. 2004. The plot thickens: new perspectives of primary cell wall modification. Current Opinion in Plant Biology 7: 296-301
Rose J.K.C., Catalá, C., Gonzalez-Carranza, Zinnia H. and Roberts, J. 2003. Plant cell wall disassembly. In The Plant Cell Wall. Annual Plant Reviews Series. Ed. J.K.C. Rose, Pub. Blackwell Publishing pp 0: 264-324
Catalá, C., Rose, J.K.C., York, W.S, Albersheim, P, Darvill, A.G. and Bennett, A.B. 2001. Characterization of a tomato xyloglucan endotransglycosylase gene that is down-regulated by auxin in etiolated hypocotyls. Plant Physiol 127: 1180-1192
Catalá, C., Rose, J.K.C. and Bennett, A.B. 2000. Auxin-regulated genes encoding cell wall modifying proteins are expressed during early tomato fruit growth. Plant Physiol 122: 527-534
Catalá, C. and Bennett, A.B., . 1998. Cloning and sequence analysis of TomCel8; a new plant endo-1,4-Β-d-glucanase gene, encoding a protein with a putative carbohydrate binding domain (Accession No. AF098292). Plant Physiol 118: 1535
Catalá, C., Rose, J.K.C. and Bennett, A.B. 1997. Auxin-induction and spatial localization of a novel endo-1,4-Β-d-glucanase and a xyloglucan endotransglycosylase in tomato hypocotyls. Plant J 12: 417-426