Biology subjects

Bajaj, R.

Publications and source records attributed to Bajaj, R..

3 recordsLinked to original sources

bioRxiv2021

Actin-based myosin XXI (13) molecular motor is involved in early phase of Leishmania cytokinesis

Leishmania genome encodes for two isoforms of myosin, but only Myosin XXI (Myo21), which is a novel form of myosin in that it contains two ubiquitin associated-like (UBA) domains towards the end of its tail structure, is expressed in both the promastigote and amastigote forms of this protozoan. Earlier studies have shown that in Leishmania promastigotes Myo21 besides localizing throughout the cell body and flagellum, it is prominently localized to the base of the flagellum. It has further been shown that this protein in the promastigotes plays an important role in regulating the cell morphology, motility, flagellum dynamics, growth and intracellular trafficking, As Myo21 depletion has been shown to result in reduced cell growth in culture, we considered it of interest to investigate whether the observed effect of Myo21 on the cell growth is mediated through its possible role in Leishmania cell division cycle. For this, we prepared heterozygous Myo21 mutants of Leishmania promastigotes (Myo21+/-cells) and then analyzed their morphology, growth and cell division cycle, using wild type Leishmania promastigotes (Myo21+/+ cells) as control. The cell division cycle was analyzed by employing flow cytometry and immunofluorescence microscopy. Flow cytometric analysis revealed that the G2/M to G1 phase transition in Myo21+/- cell is significantly delayed, as compared to Myo21+/+ cells. Immunofluorescence confocal microscopic analysis indicated that Myo21+/- cells encountered a significant delay in initiation of cytokinesis, which was mainly due to delay in the flagellar pocket division. Further analysis revealed that actin-based Myo21 motor is essentially required in the initiation phase of Leishmania cytokinesis.

cell biology↗

bioRxiv2021

Nurturing Diversity and Inclusion in AI in Biomedicine through a Virtual Summer Program for High School Students

Artificial Intelligence (AI) has the power to improve our lives through a wide variety of applications, many of which fall into the healthcare space; however, a lack of diversity is contributing to flawed systems that perpetuate gender and racial biases, and limit how broadly AI can help people. The UCSF AI4ALL program was established in 2019 to address this issue by promoting diversity and inclusion in AI. The program targets high school students from underrepresented backgrounds in AI and gives them a chance to learn about AI with a focus on biomedicine. In 2020, the UCSF AI4ALL three-week program was held entirely online due to the COVID-19 pandemic. Thus students participated virtually to gain experience with AI, interact with diverse role models in AI, and learn about advancing health through AI. Specifically, they attended lectures in coding and AI, received an in-depth research experience through hands-on projects exploring COVID-19, and engaged in mentoring and personal development sessions with faculty, researchers, industry professionals, and undergraduate and graduate students, many of whom were women and from underrepresented racial and ethnic backgrounds. At the conclusion of the program, the students presented the results of their research projects at our final symposium. Comparison of pre- and post-program survey responses from students demonstrated that after the program, significantly more students were familiar with how to work with data and to evaluate and apply machine learning algorithms. There was also a nominally significant increase in the students knowing people in AI from historically underrepresented groups, feeling confident in discussing AI, and being aware of careers in AI. We found that we were able to engage young students in AI via our online training program and nurture greater inclusion in AI.

scientific communication and education↗

bioRxiv2020

Screening a library of FDA-approved and bioactive compounds for antiviral activity against SARS-CoV-2

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19), has emerged as a major global health threat. The COVID-19 pandemic has resulted in over 80 million cases and 1.7 million deaths to date while the number of cases continues to rise. With limited therapeutic options, the identification of safe and effective therapeutics is urgently needed. The repurposing of known clinical compounds holds the potential for rapid identification of drugs effective against SARS-CoV-2. Here we utilized a library of FDA-approved and well-studied preclinical and clinical compounds to screen for antivirals against SARS-CoV-2 in human pulmonary epithelial cells. We identified 13 compounds that exhibit potent antiviral activity across multiple orthogonal assays. Hits include known antivirals, compounds with anti-inflammatory activity, and compounds targeting host pathways such as kinases and proteases critical for SARS-CoV-2 replication. We identified seven compounds not previously reported to have activity against SARS-CoV-2, including B02, a human RAD51 inhibitor. We further demonstrated that B02 exhibits synergy with remdesivir, the only antiviral approved by the FDA to treat COVID-19, highlighting the potential for combination therapy. Taken together, our comparative compound screening strategy highlights the potential of drug repurposing screens to identify novel starting points for development of effective antiviral mono- or combination therapies to treat COVID-19.

microbiology↗