Scientist, Cell Biology

The Company

FL99 is developing novel delivery technologies that will fundamentally redefine how genetic medicines can treat disease. We’re looking for future colleagues who are driven to solve incredibly hard problems in a collaborative, fast‑paced environment. If that sounds like you, we’d love to consider your application.

We are seeking an outstanding Scientist I, Cell Biology (exact title flexible based on qualifications) to join us in ideating and building the next generation of Programmable Medicines. Our mission is to completely re‑imagine nucleic acid therapeutics, casting aside long‑standing dogma to pioneer integrated innovation at the cutting edge of both payload and delivery. This is a rare and unique opportunity to be one of the first employees of a biotech startup that combines an insurgent, swing‑for‑the‑fences mindset with the backing, resources, and know‑how of one of biotech’s leading VCs.

• Ph.D. in Cell Biology, Molecular and Cell Biology, Immunology, or a related field, preferably in the context of DNA‑or RNA‑related research
• Expertise in a diverse array of cell biology techniques (described in Responsibilities below)
• Experience developing and executing cell‑based delivery assays
• Outstanding rigor and creativity in planning, executing, and interpreting experiments
• Caring deeply about your work and your colleagues
• Passion for challenging, fast‑paced, ever‑changing science

• Familiarity with molecular biology techniques, particularly those related to nucleic acid production and purification (IVT, PCR, nucleic acid extraction, HPLC, etc.)
• Familiarity with basic animal studies involving nucleic acid medicines (experimental design, CRO management, cell/tissue processing, immunohistochemistry, etc.)

• Contribute to Cell Biology innovation
  , aligned with the company’s core strategic goals. We’re looking for someone who can think critically and creatively about cell‑based assays, not merely execute them.
• Plan and execute Cell Biology experiments
  . We’re looking for someone who’s excited to roll up their sleeves and pursue hands‑on science. This is primarily a bench role, at least at the outset.
  
  Key responsibilities include:
  • Culturing and transfecting diverse mammalian cell types (primary and immortalized, human and rodent, immune and non‑immune, etc.)
  • General cell‑based assay development and screening to assess cargo delivery/uptake
    • Experience developing endosomal escape/subcellular localization assays preferred
  • Quantifying protein expression using a range of methods (luminescence/fluorescence plate‑reader assays, flow cytometry, RT‑qPCR, ELISA, Western blot, etc.)
    • Experience with in vitro translation assays (e.g., rabbit reticulocyte) preferred
  • Evaluating immune responses to novel nucleic acid cargoes (e.g., cytokine profiling at RNA/protein level)
  • Kit‑based nucleic acid extraction
  • Familiarity with fluorescence/confocal microscopy
  • Additional responsibilities may include molecular biology (e.g., nucleic acid production/purification) and contributing to animal studies
    • This role does not involve hands‑on work with live animals

• Technical expert
  :
  You have a deep background in Cell Biology. You have experience and enjoy working with a diverse array of cells and cell‑based assays, ideally in the context of nucleic acid delivery.
• Mission‑driven scientist
  :
  You have an unquenchable spirit to build something new that will create huge impact for the world.
• Relentless pioneer
  :
  You thrive in new and unknown territory - capable of charting comprehensive but actionable plans, executing rapidly and iteratively to make progress, and reliably delivering decisive readouts on time.
• Team player
  :
  You flourish in collaborative work environments with other highly skilled individuals. You readily support your colleagues’ challenges & celebrate their victories.
• Effective communicator
  :
  You not only understand the science but are capable of conveying technical information in a clear, concise, and decisive manner.

Location: Cambridge, MA

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