K.C. Kent Lloyd, DVM, PhD
Dr. Lloyd is a research physiologist with expertise in targeted mutagenesis of the laboratory mouse. His primary research focuses on the physiology of enterogastric reflexes as a model for positive and negative feedback mechanisms and pathways operating between organs. Dr. Lloyd is also involved in the development of new means for preservation and resuscitation of genetically altered mice. Dr. Lloyd serves as the Associate Director of the UC Davis Mouse Biology Program, and leads or co-leads the Murine Molecular Constructs Laboratory, the Murine Targeted Genomics Laboratory, the Murine Genetic Analysis Laboratory, and the Murine Cryopreservation and Recovery Laboratory.
Studies in the physiology of enterogastric reflexes lead to a better understanding of signals and pathways that mediate gastrointestinal functions in health and disease. Both classical as well as novel technologies are being utilized to investigate these issues. Until recently, research has been hampered by the inability to readily transfer results from molecular processes observed in cell culture to conclusions about physiology and the pathophysiology of the whole organism. With targeted mutagenesis, the expression of a single cell membrane-bound receptor can be deleted from the genome to reveal its biological significance in the growth, development, and function of an animal. The objective of Dr. Lloyd’s research is to characterize the functions of sst2 receptors, CCK A and B receptors, and ghrelin as mediators of the efferent limb of the enterogastric reflex.
Dr. Lloyd also conducts studies to develop improved means to preserve and resuscitate mutant mouse strains. The rate at which genetically-altered mouse strains are being created is exceeding the rate at which these strains can be studied in hypothesis-based biomedical research. To keep these strains alive as breeding colonies places them at risk of disease, genetic drift, and catastrophic loss. Several new methods for preservation of mouse embryos, germplasm, ovaries, and somatic tissues are being developed which ensures that a strain discontinued as a live colony can be recovered at a later time. Dr. Lloyd works on new methods for preserving sperm, including cryopreservation, freeze-drying, and evaporative drying, and the requisite techniques to ensure resuscitation by IVF and ICSI. Dr. Lloyd is also working on methods to enhance and improve somatic cell cloning as a means to preserve mouse strains that can be maintained as frozen pieces of somatic tissue from which nuclei can be recovered and used for intracytoplasmic nuclear injection (ICNI) to resuscitate the mouse strain.
A nuclear component of the UC Davis Mouse Biology Program are several of its component laboratories, including the Murine Molecular Constructs Laboratory, the Murine Targeted Genomics Laboratory, the Murine Genetic Analysis Laboratory, and the Murine Cryopreservation and Recovery Laboratory which are lead or co-lead by Dr. Lloyd. Dr. Lloyd is engaged in technology development to enhance the resource, including development of a worldwide mouse resource (the International Federation of Mouse Resources), the NIH-sponsored Mutant Mouse Regional Resource Center (MMRRC), and the NIH Knockout Mouse Project (KOMP). Dr. Lloyd is involved at many levels in all of these initiatives.
Dadi TD, Li MW, Lloyd KCK. Decreased growth factor expression through RNA interference inhibits development of mouse preimplantation embryos. Comp Med 2009;59:331-338.
Lee AYF, Lloyd KCK. Pluripotency of iPS cells derived from frozen mouse cells and tissue. Stem Cells 2009 (submitted for publication).
Skarnes WC, Liang Q, Moran JL, Qin S, Law F, Delaney L, Rairdon XY, Lloyd KCK, Bradley A. C57BL/6 embryonic stems cells for high-throughput targeting in mice. Nature Methods 2009;6:493-495.
The International Mouse Knockout Consortium, Collins FS, Rossant J, Wurst W. A mouse for all reasons. Cell. 2007;128:9-13.
Dadi TD, Li MW, Lloyd KCK. EGF and TGF-a supplementation enhances development of cloned mouse embryos. Cloning Stem Cells, 2007;9:315-326.
Dadi TD, Li MW, Lloyd KCK. Development of mouse embryos after immunoneutralization of mitogenic growth factors mimics that of cloned embryos. Comp Med 2006;56:177-184.
Escher P, Lacazette E, Courtet M, Blindenbacher A, Landmann L, Bezakova G, Lloyd KCK, Mueller U, Brenner HR. Distinguishing agrin and neuregulin functions at the neuromuscular junction. Science 2005;308:1920-1923.
Dadi TD, Li MW, Lloyd KCK. Expression levels of EGF, TGF-a and EGF-R are significantly reduced in preimplantation cloned mouse embryos. Cloning Stem Cells, 2004;6:237-253.
Austin CP, Battey JF, Bradley A, Bucan M, Capecchi M, Collins FS, Dove WF, Duyk G, Dymecki S, Eppig JT, Grieder FB, Heintz N, Hicks G, Insel TR, Joyner A, Koller BH, Lloyd KC, Magnuson T, Moore MW, Nagy A, Pollock JD, Roses AD, Sands AT, Seed B, Skarnes WC, Snoddy J, Soriano P, Stewart DJ, Stewart F, Stillman B, Varmus H, Varticovski L, Verma IM, Vogt TF, von Melchner H, Witkowski J, Woychik RP, Wurst W, Yancopoulos GD, Young SG, Zambrowicz B. The Knockout Mouse Project. Nature Genetics, 2004;36:921-924.
Lloyd KCK, Orban P, Gassmann G, Lemke G, Klein R. Neural-specific knock-out of ErbB4 using the CRE/LOX recombination system. Proc., Mouse Molecular Genetics Meeting, 1996; 326.
Co-Director, Murine Molecular Constructs Laboratory, UC Davis Mouse Biology Program
Director, Murine Targeted Genomics Laboratory, UC Davis Mouse Biology Program
Director, Murine Genetic Analysis Laboratory, UC Davis Mouse Biology Program
Director, Murine Cryopreservation and Recovery Laboratory, UC Davis Mouse Biology Program
Associate Director, UC Davis Mouse Biology Program
Associate Director, NIH Mutant Mouse Regional Resource Center (MMRRC)
NIH/NCRR Infrastructure and Resources Study Section
UC Davis MCIP and Comp Path Graduate Groups