Book excerpt: Modulation of Protein Function, Volume XIII, presents the proceedings of the ICN-UCLA Symposium on Molecular and Cellular Biology held in Keystone, Colorado, from February 25-March 2, 1979. The symposium aimed to bring together workers from several fields, all of which deal with the modulation of protein function. The discussion of representative metabolic control systems, ranging from single enzyme responses to complex regulatory cascades, and the control of photosynthesis and of protein synthesis and enzyme inactivation, dealt with the general topic at perhaps its most fundamental cellular level. Modulations and conformational changes in proteins that underlie higher-level interactions, such as those involved in cyclic nucleotide function, sensing and chemotactic response to foreign materials, and the complement system, were also described. Two talks dealt with potential clinical relevance of phenomena of the types described by other participants. The book is organized into nine parts with papers covering the following topics: modulation of enzymes of intermediary metabolism (Part I); modulation and inactivation (Part II); photosynthesis and storage polysaccharides (Part III); cascade systems (Part IV); protein phosphorylation (Part V); methylation in chemotaxis (Part VI); cyclic GMP and cyclic CMP (Part VII); protein synthesis (Part VIII); and clinical implications (IX).