Gene Block

University of Virginia

In 1978, Block became a member of the faculty in the Department of Biology of University of Virginia. Here, Block served as the vice provost for research from 1993 to 1998, vice president for research and public service from 1998 to 2001, and then in 2001 he was appointed as executive vice president and provost. Furthermore, during this time from 1991 to 2002, Block also served as the founding director of the National Science Foundation Science and Technology Center in Biological Timing.^[5]

According to Block, “The center raised the national visibility of the University in biological and medical research, and gave us reputational leverage in the U.S. as well as in Europe and Japan... Most importantly, the center's scientific accomplishments have been spectacular. We’ve done some high-risk research that has paid off greatly; some of it has fundamentally changed our understanding of biological processes.”^[6]

One of the center's biggest advances, largely by Joseph Takahashi, was the development of a mutant mouse that allowed for the identification and cloning of the “Clock” gene for the biological clock in a mouse in 1997. This was the first such gene to be identified at the molecular level in a mammal. This groundbreaking discovery was a result of the Clock Genome Project, which uses "forward genetics" to discover the genes regulating circadian clocks in mice, fruit flies, and plants. In addition, this work also led to the discovery of many other genes that regulate the biological clock.^[7]

In 1997 and 1998, the reputable journal Science ranked the findings of the NSF Center in Biological Timings among the top 10 in biological research breakthroughs.^[7]

Three of the NSF Center investigators, Jeffrey C. Hall, Michael Rosbash and Michael W. Young,^{[clarification needed]} received the 2017 Nobel Prize in Physiology or Medicine “for their discoveries of molecular mechanisms controlling the circadian rhythm.”^[8]

University of California, Los Angeles

Block was appointed Chancellor of UCLA in 2007. His selection was announced on 21 December 2006, succeeding interim office holder Norman Abrams on 1 August 2007.^[9]

On February 24, 2014, Block published an open letter to the campus community, expressing his opposition to Proposition 209, stating that the proposed merit-based selection system would damage diversity on campus.^[10]

He has been widely criticized for the 2022 suspension of highly awarded professor of ecology Priyanga Amarasekare without documentation, viewed as retaliation for her calls for reform of a culture of discrimination at UCLA.^[11]

In his inaugural address at UCLA, Block shared that his top priorities are to advance academic excellence, financial stability, diversity and civic engagement.^[12] He has called for UCLA to deepen its engagement with Los Angeles and to increase access for students from underrepresented populations.^[13] Under Block's leadership, UCLA has seen an increase in student diversity on campus thanks to innovative efforts to recruit in diverse communities, and in 2015, UCLA reached pre-California Proposition 209 levels, enrolling 279 African American freshmen, on par with the African American share of California public high school graduates.^[14] UCLA has also increased the number of low- to middle-income students enrolled.^[15]

In 2019 UCLA was named the number one public university in the nation for the third consecutive year^[16] and is consistently the most applied-to university, with more than 113,000 freshman applications for fall 2018.^[17]

Block's push for entrepreneurship on campus has fostered innovation and resulted in UCLA as the top university for creating startups based on campus research.^[18] Additionally, to foster a deeper commitment to Los Angeles among UCLA students, Block oversaw the formation of the annual Volunteer Day event, in which thousands of students volunteer in schools, parks, food banks, veterans’ clinics and elsewhere at the beginning of each academic year.^[19] Block also implemented UCLA's two Grand Challenges, which are aimed at understanding, treating and preventing depression worldwide,^[20] and moving Los Angeles toward 100 percent renewable energy, 100 percent locally sourced water and enhanced ecosystem health by 2050.^[21]

During his tenure, Block has faced the challenge of steering UCLA through a severe budget crisis and tuition increases.^[22] To address reductions in state funding and advance his priorities, Block is leading the largest fundraising campaign by a public university, aiming to raise $4.2 billion to support student scholarships and fellowships, research projects and new construction on campus in honor of UCLA's centennial in 2019.^[23]

Block holds UCLA faculty appointments in psychiatry and bio-behavioral sciences in the David Geffen School of Medicine and in integrative biology and physiology in the College of Letters and Science.^[24]

On April 25, 2024, a pro-Palestinian occupation protest began at UCLA to protest the administration's investments in Israel amid the Israel–Hamas war.^[25] On May 1, violent clashes were reported on the UCLA campus in which groups of counter-demonstrators supporting Israel attacked pro-Palestinian protesters. The clashes began shortly after Block declared that the pro-Palestinian encampment was "unlawful" and students who remained would face disciplinary action.^[26] In the days after the incident, senate faculty members from the departments of History,^[27] English, Comparative Literature, and Writing Programs,^[28] Asian American Studies,^[29] World Arts and Cultures/Dance,^[30] Disability Studies,^[31] Gender Studies,^[32] Information Studies,^[33] Chicano/a and Central American Studies,^[34] Art,^[35] Art History,^[36] Philosophy, ^[37] African American Studies,^[38] Sociology,^[39] Anthropology,^[40] and Society & Genetics,^[41] the Center for the Study of Women,^[42] in addition to subsets of faculty from the departments of Epidemiology,^[43] Social Welfare,^[44] Education,^[45] Mathematics,^[46] Design Media Arts,^[47] the Luskin School of Public Affairs^[48] (and its graduate students),^[49] the David Geffen School of Medicine,^[50] and the School of Theater, Film, and Television,^[51] faculty and staff from the broader UC system,^[52] alumni groups,^[53] the representatives of the Undergraduate Students Association (student government),^[54] and a joint statement by the California Federation of Teachers and the University Council-AFT^[55] (which respectively represent educators and classified professionals, and UC librarians and non-Senate faculty), along with an individual statement from UC-AFT Local 1474,^[56] issued calls for votes of no confidence and/or the immediate resignation of Block due to his handling of the conflict. A supermajority of voting UC-AFT Local 1474 members voted to express no confidence in Block's leadership.^[57] Ultimately, opponents of Block failed to force him to resign, as neither censure nor a vote of no confidence passed in the UCLA Academic Senate on May 16, 2024.^[58][59]

On August 3, 2023, Block announced his impending retirement nearly a year in advance.^[60] He officially stepped down on July 31, 2024, ending his seventeen-year tenure as chancellor.

Cell-autonomous circadian pacemakers

While at the University of Virginia, Block worked extensively with his graduate student, Douglas G. McMahon, the 1986 winner of the Society for Neuroscience's Donald B. Lindsley Prize in Behavioral Neuroscience, on the functioning of the circadian pacemaker system at the cellular level in Bulla gouldiana. In 1984, Block's students conducted a continuous 74-hour intracellular recording in constant darkness that demonstrated that basal retinal neurons (BRN) in the Bulla eye exhibit clear circadian rhythms. These rhythms were also shown to be correlated one-for-one with compound action potentials produced by the optic nerve.^[61] The change in membrane potential of the BRNs, which are electrically coupled, were shown to precede or occur simultaneously with the increased compound action potential frequency. An increase in firing frequency, and depolarization of the BRNs, was seen during the day, and the reverse at night. These results demonstrated that the BRNs were at minimum an output for the pacemaker pathway and provided evidence that they were good candidates for being circadian pacemaker neurons.

This research was expanded several years later by a breakthrough study published in Science in which Stephan Michel and others working in Block's laboratory demonstrated that circadian rhythms in BRN membrane conductance could persist spontaneously in isolated BRNs.^[62] These spontaneous circadian rhythms were shown for BRNs in isolation from other retinal cells and in isolation from each other. They showed that these circadian rhythms in membrane conductance were caused primarily by a potassium ion current. BRNs in isolation demonstrated the same patterns shown in Block's previous work in which membrane conductance decreased at dawn and increased at dusk. That similar patterns were seen in isolated cells as in previous multiple cell cultures provided the first strong evidence that individual neurons possessed the capacity to generate circadian rhythms. This research definitively concluded that BRNs are both necessary and sufficient for photoentrainment in Bulla.

Necessity of calcium flux for rhythmicity

Block and colleagues hypothesized that ion movement across cell membranes plays a role in the generation of circadian rhythms. In 2005, his lab measured rhythms in rat suprachiasmatic nuclei (SCN) in various concentrations of calcium ions. Block found that as calcium concentration decreased, thus lowering the transmembrane ion movement, the amplitude of circadian rhythmicity also decreased.^[63] With no calcium added, there was no circadian rhythm at all. Block's lab repeated the experiment with rat liver tissue and mouse SCN tissue and found the same results in each case. This demonstrated that across species and tissues, transmembrane calcium flux is necessary for the generation of circadian rhythms. However, there are still some questions about the function of calcium flux. In this experiment, Block also tried adding calcium channel Blockers to the tissues. Rhythmicity did disappear, but it took several cycles, and it is unknown why rhythmicity was not immediately abolished. In addition, Block suspects that calcium flux plays a role in the entrainment of the mammalian clock to the environment, similar to its role in mollusk entrainment.

Effects of aging on the circadian clock

Block has also studied the effect that aging has on the circadian system, collaborating with other leading chronobiologists including Michael Menaker. In 2002, he studied rhythmicity in rats of various ages and found that aging affected rhythmicity differently in different tissues. In the SCN, the intrinsic period shortened with age, while lung tissue often became arrhythmic (showing sporadic activity) and pineal and kidney tissues became phase advanced.^[64] In 2008, Block exposed rats of various ages to different light cycles, and found that phase advances took longer in the SCN in old rats than in young rats, but pineal tissues advanced faster in older rats. Liver tissues did not phase shift at all when the light cycle was advanced.^[65] These studies together have shown how complex the aging process is in the circadian system. Block notes that some, though not all, of these changes are likely influenced by diminishing synchronizing signals from the SCN. In 2006, Block observed that jetlag significantly increased the death rate in older mice, which highlights the medical importance of understanding the aging process of the circadian system.^[66]