About the roleWe are hiring a hands-on
Senior Research Associate to build and run the cell-based assays and engineered cell lines behind our drug discovery programs. You will work day to day with a senior scientist in R&D, owning bench execution while helping shape assay strategy.
Your core work: maintaining mammalian cell lines, engineering them with RNP-based CRISPR (knockouts and knock-ins), generating validated stable lines, and turning them into robust functional assays. The data you generate feeds directly into AI and physics-based compound design, so quality and reproducibility matter as much as throughput.
Applicants must be authorized to work for any employer in the U.S. We are unable to sponsor or take over sponsorship of an employment Visa at this time.
Requirements- Bachelor's or Master's degree in biology, cell biology, bioengineering, biochemistry, immunology, or a related discipline, or an equivalent combination of education and experience.
- Relevant hands-on laboratory experience
- Demonstrated mammalian cell culture experience with strong aseptic technique, including routine maintenance of multiple lines in parallel.
- Hands-on experience with CRISPR gene editing: knockout generation, and ideally knock-in, with validation of edited clones.
- Experience with transient transfection, and with generating and validating stable cell lines, including clonal selection and banking.
- Experience executing at least one cell-based assay readout, such as flow cytometry, plate-based viability, reporter, or proliferation assays.
- Ability to analyze data, assess assay quality, communicate findings clearly, and work in a collaborative, multidisciplinary setting.
- Commitment to laboratory safety, research integrity, accurate documentation, and responsible handling of biological materials.
Nice to have qualifications- Hands-on RNP-based CRISPR knockout and knock-in using Lonza Nucleofector platforms (4D-Nucleofector or equivalent), including program and buffer selection for the target cell type.
- Experience with high-throughput or automated assay platforms, including 96- or 384-channel electronic pipetting systems and benchtop pipetting robots (INTEGRA VIAFLO, MINI 96, VOYAGER, ASSIST PLUS or comparable), and multimode plate readers.
- Experience developing or optimizing BRET, TR-FRET/HTRF, or related proximity-based assay formats .
- Molecular biology bench skills: construct and primer design, cloning, qPCR or digital PCR, Western blot.
- Drug discovery experience in biotech or pharma, including work on a target-to-lead or lead-optimization program.
- Familiarity with assay qualification concepts: design of experiments, dose-response analysis, curve fitting, acceptance criteria, and statistical assessment of assay variability.
- Experience with neuronal or other CNS-relevant cell models. .
- Experience with multiplexed editing, including triple knockouts or combined knockout and knock-in lines.
Key responsibilitiesMammalian cell culture- Culture, expand, and maintain mammalian cell lines under strict aseptic technique; monitor health, viability, density, and passage history.
- Maintain cryopreserved stocks, run mycoplasma and identity checks, and keep accurate lineage records.
Genome engineering- Optimize RNP-based CRISPR/Cas editing in mammalian cell lines: single and double knockouts.
- Design and execute targeted knock-in strategies, including donor design, delivery optimization, and editing-efficiency assessment.
- Genotype and validate edits by sequencing, qPCR or digital PCR, and protein-level readouts.
Stable cell line generation- Perform transient transfections to test constructs quickly, optimizing reagent, nucleic acid amount, and harvest timing, and confirming expression before committing to a stable line.
- Generate stable lines using viral and non-viral delivery; perform clonal selection, expansion, functional validation, and banking.
- Characterize clones for expression level, assay performance, and stability over passage.
Cell-based assay development- Develop, optimize, and run functional assays: plate-based, reporter and proximity-based assays; flow cytometry; and other cellular functional readouts.
- Optimize seeding density, stimulation conditions, dose range, incubation time, controls, and acceptance criteria to improve sensitivity, dynamic range, and reproducibility.
- Prepare test articles, reagents, controls, and assay plates according to established protocols and study plans .
Data, documentation, and communication- Analyze dose-response data, fit curves, assess assay quality (Z', signal window, variability), and flag trends, outliers, and deviations.
- Keep complete, timely records in the electronic lab notebook, consistent with data-integrity expectations.
- Present results at team meetings and contribute figures and data to technical reports.
Lab operations- Troubleshoot routine assay and culture problems, escalate significant deviations, and partner with colleagues to improve method robustness and transferability.
- Support reagent preparation, inventory, equipment upkeep, sample tracking, and safety compliance.
- Manage assigned work to agreed timelines.
Working conditionsThis is a primarily onsite, laboratory-based position in South San Francisco. The role involves regular use of standard laboratory equipment and PPE, work with biological samples and research reagents, prolonged standing or sitting, repetitive hand motions, and moving laboratory supplies up to approximately 25 pounds, with reasonable accommodation as needed. Occasional work outside standard business hours may be required for time-sensitive experiments. Travel is minimal.
Benefits- Competitive compensation package with meaningful equity.
- Comprehensive health, dental, and vision coverage.
- Annual team gatherings and company events.
- Free lunch, snacks, beverages, and onsite gym access (for in-office employees).
