Howard Robert Horvitz ForMemRS NAS AAA&S APS NAM (born May 8, 1947) is an American biologist. His research on the nematode worm Caenorhabditis elegans earned him the 2002 Nobel Prize in Physiology or Medicine, along with Sydney Brenner and John E. Sulston. Their important discoveries about how genes control the growth of organs and the process of programmed cell death have helped medical research and provided new insights into how many diseases develop.

Early life and education

Horvitz was born in Chicago, Illinois, to Jewish parents. His mother, Mary R. (Savit), was a school teacher, and his father, Oscar Freedom Horvitz, worked as an accountant for the GAO. He studied mathematics at the Massachusetts Institute of Technology, where he joined Alpha Epsilon Pi. During summers, he worked for IBM. At first, he helped connect parts of machines used for accounting, and later, he assisted in creating IBM's Conversational Programming System.

In his senior year, Horvitz took his first biology classes. His professors encouraged him to continue studying biology in graduate school, even though he had not taken many biology courses before. After finishing his undergraduate studies in 1968, he began graduate studies in biology at Harvard University. There, he researched how T4 caused changes in E. coli RNA polymerase under the guidance of Walter Gilbert and James Watson. He earned his PhD in 1974.

Career

In 1974, Horvitz took a position at the Laboratory of Molecular Biology (LMB) in Cambridge, England. He worked with Sydney Brenner and John Sulston, who later won the Nobel Prize, on the genetics and cell lineage of C. elegans. In 1978, Horvitz was offered a faculty position at MIT. He is now a professor of biology and a member of the McGovern Institute for Brain Research. He is also an Investigator of the Howard Hughes Medical Institute. Horvitz serves as the chair of the board of trustees for the Society for Science & the Public. He is also a member of the USA Science and Engineering Festival's advisory board.

Research

At LMB, Horvitz worked with Sulston to study every cell division that happened in the body of a developing worm, except those in the gonads. In 1977, they wrote a full report describing these cell divisions. Later, with Sulston and Martin Chalfie, Horvitz began studying how certain genetic changes affected cell divisions. They first examined mutants with unusual cell lineages and then looked for genes that controlled these lineages. In 1981, they discovered and described the gene lin-4, which causes changes in the timing of when cells develop into specific types.

At MIT, Horvitz continued studying cell lineages and cell development using the roundworm C. elegans. He investigated whether genes controlled a process called apoptosis, or programmed cell death. In 1986, he identified the first genes linked to cell death: ced-3 and ced-4. He showed that these genes were necessary for cells to die properly. He also found that another gene, ced-9, prevents cell death by interacting with ced-3 and ced-4. He discovered other genes that help remove dead cells from the body. Horvitz found that humans have a gene similar to ced-3.

In later research, Horvitz used C. elegans to study how genes control animal development and behavior. He also connected findings from the worm to human diseases, such as cancer and neurodegenerative disorders like amyotrophic lateral sclerosis (ALS). He further explained the steps involved in programmed cell death and identified important parts of this process, including EGL-1, a protein that starts apoptosis by blocking CED-9. He also studied genes like ces-1, ces-2, and ced-8, which help control when cells die. Horvitz continued researching changes in the timing of cell development and worked on topics like how cells send signals, how bodies form shapes, and how nerves develop. He collaborated with Victor Ambros and David Bartel to study all the more than 100 microRNAs in the C. elegans genome.

Works

Horvitz has more than 255 published works, has been cited more than 49,000 times, and has an h-index of 108.

• Sulston, J.E.; Horvitz, H.R. (March 1977). "Post-embryonic cell lineages of the nematode, Caenorhabditis elegans." Developmental Biology. 56 (1): 110–156. doi: 10.1016/0012-1606(77)90158-0. PMID 838129.
• Ellis, Hillary M.; Horvitz, H. Robert (28 March 1986). "Genetic control of programmed cell death in the nematode C. elegans." Cell. 44 (6): 817–829. doi: 10.1016/0092-8674(86)90004-8. PMID 3955651. S2CID 44031839.
• Ellis, R E; Yuan, J; Horvitz, H R (November 1991). "Mechanisms and Functions of Cell Death." Annual Review of Cell Biology. 7 (1): 663–698. doi: 10.1146/annurev.cb.07.110191.003311. PMID 1809356.
• Yuan, J; Shaham, S; Ledoux, S; Ellis, HM; Horvitz, HR (19 November 1993). "The C. elegans cell death gene ced-3 encodes a protein similar to mammalian interleukin-1 beta-converting enzyme." Cell. 75 (4): 641–652. doi: 10.1016/0092-8674(93)90485-9. PMID 8242740.
• Hengartner, MO; Horvitz, HR (25 February 1994). "C. elegans cell survival gene ced-9 encodes a functional homolog of the mammalian proto-oncogene bcl-2." Cell. 76 (4): 665–76. doi: 10.1016/0092-8674(94)90506-1. PMID 7907274. S2CID 29437409.