Charles Lambert - US grants

This award will support U.S. participation in a seminar on the "Developmental Biology of the Ascidian" organized jointly by Professor Charles Lambert of California State University, Fullerton and Dr. Takaharu Numakunai of Tohoku University, Japan. Six U.S. researchers will meet with Japanese scientists in August 1988 at the Asamushi Marine Biological Station of the Tohoku University. Topics of ascidian biology to be discussed include: the molecular basis of fertilization and cell differentiation during cleavage, control of the reproductive cycle, controls of colony formation and recognition, the accumulation and function of metal ions during development, the mechanism of metamorphosis, the formation of complex extracellular structures, and the nature of substances made by ascidians which are toxic to viruses, bacteria and tumor cells. Ascidians, as the most primitive of the living chordates, are ideal organisms for studying basic questions in developmental biology and may teach us much about the development and evolution of vertebrates. Remarkable strides have been made over the last five years in our understanding of many aspects of ascidian development. This joint U.S.-Japan seminar will provide a much-needed forum for the exchange of research results and ideas between ascidian biologists in our two countries.

Dr.Lambert and Dr.Goode will study a block to polyspermy in the Ascidian egg. According to their model, the sperm bind to glycosides on the vitelline coat of the egg. An increase in the number of sperm binding to the vitelline coat is followed by a rapid decline. This decline in binding helps insure that only a single sperm enters the egg. Sperm binding is inhibited by the Na+-dependent release of a glycosidase that modifies the vitelline coat sperm receptors. They hypothesize that the glycosidase is initially linked to the egg membrane and is rapidly discharged at fertilization. The fact that detergents and Phospholipase C can free the enzyme from the unfertilized egg suggest that the enzyme is linked to a membrane phospholipid. Their model includes linkage of the glycosidase to a phosphatidylcholine and the Na+-dependent activation of a phospholipase that causes enzyme release. The glycosidase and phospholipase will be isolated and extensively characterized. Antibodies will be prepared to both proteins for ultrastructural enzyme localization. The mechanism of release will be probed through the use of phospholipase agonists and antagonists and also through the direct measurement of phospholipase activity in unfertilized and fertilized eggs. The role of G proteins and ions in Ascidian egg activation will also be probed. %%% Although millions of sperm are produced for each egg, if more than a single sperm enters the egg,cleavage is grossly abnormal and death is inevitable. As a consequence, blocking the entry of additional sperm is of critical importance to fertility. Dr.Lambert and Dr. Goode will further the understanding of this phenomenon by studying the molecular details of sperm entry and blocking in the Ascidian system.

9317873 Koch Light microscopic studies comprise the cornerstone of cell biological investigations. No cell biology research laboratory should be without access to the full complement of modern light microscopy techniques for analyzing cell structure and function. This proposal seeks matching funds to purchase one inverted microscope and one upright microscopes each having phase contrast, epifluorescence and differential interference contrast optics with still or video photomicrography capabilities all to be coupled to a state-of-the-art image acquisition and analysis system and a dedicated image processing computer. This instrumentation will form the nucleus of a new Light Microscopy Laboratory. Its acquisition continues our effort to enhance research opportunities for faculty, graduate and undergraduate students studying cell biology. Microscopes of the types requested are not readily available at present. Researchers must borrow time on a single research-grade upright microscope or compete with students in five courses for four student grade upright microscopes--no research-grade inverted microscope or image acquisition/processing instrumentation is available at all. The requested instrumentation will promote studies of cell biology of tunicate sperm and egg activation, axonal transport of mRNA in sea hare neurons, and protection to UV damage in plants as well as five other minor projects.

[unreadable] DESCRIPTION (provided by applicant): One of the major goals of PAS-03-122, Frailty in Old Age: Pathophysiology and Interventions, is to enhance the development and evaluation of unique interventions that target processes that appear to play an important role in the mechanism(s) of the development and progression of frailty. Frailty has been defined as consisting of low muscle strength, slow walking speed, weight loss, and low physical activity. Clearly, sarcopenia, or the age related loss of muscle mass and muscle strength contributes substantially to the muscle strength and walking speed decrements of frailty. Beta-two adrenergic agonists (B2A) significantly increase muscle mass in the elderly; however, the mechanism(s) for this increase in muscle mass in humans is/are not known. We will examine: 1) the effects of 2.5 and 8.5 days of albuterol administration (16 mg/24h) on skeletal muscle protein synthesis (MPS) and the mRNAs for insulin like growth factor II, and Ca2+ dependent proteolysis using Real Time PCR as well as the phosphorylation status of P70 S6 Kinase using the Western Blot technique in elderly (age 60-85) men and women who have body mass indices that correspond to the presence of sarcopenia. Animal data suggest that B2A stimulate MPS for 2-3 days with inhibition of protein degradation occurring at later time points. The 8.5 day measurement will be to determine whether MPS remains elevated later in humans. Elucidating, the way in which B2A affect muscle protein metabolism may possibly lead to other therapeutic strategies to target specific components of protein synthetic and/or protein degradative pathways that are activated or deactivated by B2A. Additionally, if we determine the primary site of action of B2A we will able to hypothesize whether B2A will likely work in different aging related muscle wasting conditions. Because of the exploratory nature of this study the R21 granting mechanism is appropriate. Muscle mass loss as a result of aging is a major problem. Some strategies for attenuating muscle mass loss such as testosterone replacement may have unwanted side effects. Albuterol, an FDA approved drug, has been shown to increase muscle mass in the elderly with minimal side effects. Because this is the case, it is important to know the mechanism by which albuterol increases muscle mass in humans so that similar strategies may be developed. By finding the precise target(s) of albuterol action alternative strategies can be developed to attenuate the incidence of sarcopenia. [unreadable] [unreadable] [unreadable]