Early in his presidency, Theodore Roosevelt sparked a scandal when he invited the African-American educator Booker T. Washington to dine with him and his family; he was the first president ever to entertain a black man in the White House. In 1886, Roosevelt ran unsuccessfully for mayor of New York City. Two years later, President Benjamin Harrison rewarded Rooseveltâs service to the Republican Party with a job on the U.S. Civil Service Commission; he was reappointed by Harrisonâs successor, Grover Cleveland.
1 Signaling involves a receptor, the transduction of information from the cell surface to inside the cell, and subcellular systems that make a response. 2  Receptors are proteins with specific binding sites for signaling molecules called ligands. All cells are equipped with elaborate systems for receiving signals from their environment. 2  The mechanisms involved in cell signaling are particularly crucial for understanding multi-cellular organisms, and are an important in many diseases.
Cells receive information from their environment through a class of proteins known as receptors. The information is then processed through signaling pathways and decoded in the nucleus and other areas of the cell.To understand cell signaling, we need to understand the spatial and temporal dynamics of both receptors and the components of signaling pathways.ell nuclei are labeled blue. All living cells sense and respond to their environment by a set of mechanisms known as cell signaling â part of a complex system of communication that governs basic cellular activities and coordinates cell actions. To understand cell behavior, we must understand cell signaling.