the processes of self-renewal and differentiation of stem cells in C. elegans, with the hope of gathering more information on the components and steps involved in each mechanism.
The activities of self-renewal and proliferation are key features that are tightly controlled by various external and internal signals, which vary according to their effective distance, wherein some signals are directly secreted onto the target protein whereas others can elicit a response despite their location from a distal region of the body. C. elegans has served as a highly useful animal model to study the mechanisms behind the survival and maintenance of stem cells. Although it presents similarities with other model organisms, it also possesses unique features that are still useful in the elucidation of tissue homeostasis.
Rhea U. Vallente
Independent Scholar
See Also: Adult Stem Cells: Overview; Cancer Stem Cells: Overview; Stem Cell Niche.
Further Readings
Cha, D. S., U. S. Datla, S. E. Hollis, J. Kimble, and M.-H. Lee. “The Ras-ERL MARK Regulatory Network Controls Dedifferentiation in Caenorhabditis elegans Germlines.” Biochimica et Biophysica Acta, v.1823 (2012).
Hyenne, V., N. T. Chartier, and J.-C. Labbe. “Understanding the Role of Asymmetric Cell Division in Cancer Using C. elegans.” Dev Dynam, v.239 (2010).
Minor, P. J., T.-F. He, C. H. Sohn, A. R. Asthagiri, and P. W. Sternberg. “FGF Signaling Regulates Wnt Ligand Expression to Control Vulval Cell Lineage Polarity in C. elegans.” Development, v.140 (2013).
Racher, H. and D. Hansen. “PUF-8, a Pumilio Homolog, Inhibits the Proliferative Fate in the Caenorhabditis elegans Germline.” G3 (Bethesda), v.2 (2012).
California
California
166
170
California
California is generally considered to offer the most supportive and permissive environment for stem cell researchers in the United States. As early as 1981, California researchers collaborated with researchers at Cambridge University in the United Kingdom to cultivate mice embryonic stem cells from explanted inner cell mass cells. California was the first state to adopt an official position of support for stem cell research. When federal funding was severely restricted for embryonic stem cell research because of the ethics debate over using aborted or discarded fetuses as the chief source of stem cells, California expressed its support for stem cell therapies that could save lives by passing Proposition 71, the California Stem Cell Research and Cures Bond Act. Proposition 71 allotted $3 billion in state funding over a 10-year period for stem cell research and created a state stem cell agency, the California Institute for Regenerative Medicine (CIRM).
California’s support for stem cell research has attracted some of the most respected scientists in the world to the state, enticing them away from other American institutions and from other countries. Between 2005 and 2006, at least 30 notable stem cell researchers were recruited to work in California institutions. Private companies involved in stem cell research and therapies are also attracted to California, further swelling the state’s talent pool. The ban restricting the use of federal funds for stem cell research was lifted in 2009 by President Barack Obama, and California began receiving federal funds for stem cell research. By 2014, of the first 14 agencies to receive funding from CIRM, nine were either recruiting patients for clinical trials or were preparing to do so. One study on human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS) and another on congestive heart failure were already under way. Upcoming clinical trials involve treatments for leukemia and solid tumor cancers, degenerative eye disease, type 1 diabetes, sickle cell disease, and a severe blood disorder.
Background
In 2001, as a Republican strongly opposed to abortion, President George W. Bush handed down major restrictions on using federal funds to conduct stem cell research. In response, a California coalition that included Hollywood producers, actors, scientists, 22 Nobel laureates, 50 patent advocacy groups, private foundations such as the Christopher Reeve Foundation and Michael J. Fox Foundation, technology giants such as Microsoft founder Bill Gates, Google inventor John Doerr, and eBay founder Pierre Omidyar, real estate developer Robert Klein II, and Republican millionaire Thomas Coleman began lobbying for the right of California voters to decide for themselves whether the state should allot funds for stem cell research. Supporters argued that Proposition 71 would not only improve the economy by creating new jobs and bringing new taxpayers to California but would ultimately make health care more affordable within the state. Voters overwhelmingly supported the measure, paving the way for California to become a global center for stem cell research. A major feature of Proposition 71 was the establishment of the California Institute for Regenerative Medicine.
Opposition to the measure was spearheaded by conservatives and the Roman Catholic Church. Immediately after passage of Proposition 71, critics of the measure began filing lawsuits in the hope that they could delay action long enough to completely block state funding for stem cell research. However, local philanthropists stepped in with loans and grants. Irwin Jacobs, the founder of Qualcomm, and John Moores, the owner of the San Diego Padres, issued $45 million in loans, and Governor Arnold Schwarzenegger, a Republican, earmarked $150 million in state loans to get CIRM in operation.
California Institute for Regenerative Medicine
The California Institute for Regenerative Medicine (CIRM) is governed by a 29-member board comprised of stem cell researchers, business leaders, and patient advocates. CIRM monitors stem cell activity within the state and provides funds for stem cell research. Its stated mission is to increase knowledge of stem cell therapies designed to mitigate suffering from disease and injury while conforming to the highest medical standards governing the field of stem cell research. The institute was established by Californians as part of Proposition 71. Because of lawsuits that blocked bond funds, it was not until 2006 that CIRM opened its doors in San Francisco.
By early 2014, CIRM had made 606 awards totaling $1,748,625,009 to fund stem cell research at California’s universities, medical facilities, foundations, institutions, and private companies. CIRM also awards funds to individual researchers. CIRM sponsors the Regenerative Medicine Consortium, which is comprised of private companies, academic institutions, and funding entities. The consortium provides members with a forum for sharing information and serves as a technical resource.
The lion’s share (69 percent) of CIRM resources is dedicated to funding stem cell research. Eleven percent is earmarked for training, and the remaining 20 percent is used to run the facility. Three-fourths of research resources are directed toward developing treatments for neurological disorders (34 percent), heart/vascular disease (15 percent), blood immune disorders (14 percent), and cancer (12 percent). Other research resources are devoted to sensory organs (6 percent), bone/cartilage disorders (5 percent), muscular disorders (5 percent), diabetes (3 percent), GI/liver (3 percent), reproductive diseases (2 percent), and kidney/urinary (1 percent).
CIRM has formed collaborative relationships with a number of stem cell agencies, including some in other countries. Collaborators include France’s Agence Nationale de la Recherche, the AIDS Healthcare Foundation, Spain’s Andalusian Initiative for Advanced Therapies and the Ministry of Science and Innovation, Canada’s Cancer Stem Cell Consortium, China’s Ministry of Science and Technology, Germany’s Federal Ministry of Education and Research, Japan’s Science and Technology Agency, the Juvenile Diabetes Research Foundation, Keystone Symposia of Molecular and Cellular Biology, the Maryland Technology Development Corporation, the United Kingdom’s Medical Research Council, the Muscular Dystrophy Association, Australia’s National Health and Medical Research Council and the State of Victoria, the United States National Institutes of Health, the New York Stem Cell Foundation, Brazil’s São Paulo Research Foundation, Scottish Enterprise,