Sally G Pasion

Pasion

Sally G Pasion

( She/Her/Hers )

Associate Professor
Biology, College of Science and Engineering

Email:
pasion@sfsu.edu
Phone Number:
(415) 405-0736
Location:
HH 668C

At SF State Since:

2001

Office Hours:

Sunday: Closed
Monday: Closed
Tuesday: 9:00-10:00on Zoom. Please make appointment on
Wednesday: 14:30-15:30Navigator: https://sfsu.campus.eab.com/pal/5tVebeuVMs
Thursday: Closed
Friday: Closed
Saturday: Closed

Bio:

Sally Pasion joined the faculty at San Francisco State in 2001, and is currently an Associate Professor of Biology, and teaches general education Biology courses to nonmajors, genetics and molecular biology to majors, and cell & molecular techniques to graduate students.  Her research interests include DNA replication and telomere maintenance in Schizosaccharomyces pombe, the fission yeast, which is an excellent system for training undergraduate and graduates students in basic cell biology, molecular biology, and microbiology.  Her research has been funded by a National Institutes of Health-National Cancer Institute UCSF/SFSU Collaborative-Cancer Research and Research Training Grant and a National Institutes of Health MBRS-SCORE Grant.  

She completed a B.A. in Chemistry at Harvard University, and then worked as a research assistant in the Laboratory of Pharmacology at the Harvard School of Dental Medicine, studying gene amplification in pituitary tumor cells. She received a Ph.D. in Biology from UCLA in 1995, studying a mitochondrial topoisomerase and the cell cycle regulation of DNA replication in the trypanosome Crithidia fasciculata.  She studied DNA replication in the fission yeast, at the Salk Institute for Biological Studies for her postdoctoral studies until 2000.  

Personal Pronouns: she/her/hers

CV:

 

Pasion Lab Research

The regulation of the replication of the genome is critical in the basic process of cell division. The genetic material must be duplicated correctly, completely, and at the appropriate time during the cell division cycle. Regulation of this process is essential to maintain genomic integrity and to prevent aneuploidy or genetic instability, which are hallmarks of cancer. Of further importance is understanding how the cell responds to replication stress induced by the encounter of the replication complex with a modified nucleotide or other form of aberrant DNA structure (DNA damage) or with a transcription complex.

We use the single-celled organism Schizosaccharomyces pombe, or fission yeast, as a model for the study of eukaryotic DNA replication. Fission yeast is an excellent model system to address questions relevant to S phase regulation because of the similarity of its cell cycle regulation to that of other eukaryotes, the tractability of its genetics and cell biology, the availability of molecular biology tools for manipulation, and the sequencing of its genome.

The focus of my laboratory centers on the analysis of cdc24+, an essential fission yeast gene that is required for genomic integrity and likely has a role in late S phase. cdc24+ encodes a novel protein with no obvious homologs in the genome databases, though the homolog exists in the related fission yeasts (S. octosporus, S. japonicus, and S. cryophilus). The fission yeast mutant, cdc24-M38, was originally identified in the cell division cycle (cdc) mutant screen thirty years ago by Kim Nasmyth and Paul Nurse as a mutant defective in the DNA synthesis phase, or S phase, of the cell cycle (Nasmyth and Nurse, 1981). Loss of cdc24 function results in [1] the arrest of the mutant cells with a single nucleus and an apparently replicated genome, and [2] chromosome breakage, which is uncharacteristic of S phase mutants (Gould et al., 1998).

Overall, our approach to defining the role of Cdc24p in genome maintenance utilizes genetics, molecular biology, cell biology, and biochemistry approaches. Preliminary work has indicated that this cdc24 mutant has genetic interactions with a group of proteins involved not only with DNA replication but also with DNA repair. We have identified several suppressors of the cdc24 temperature sensitive growth phenotype, including the fission yeast gene, dna2+, a DNA helicase/endonuclease (Kang et al., 2000). These interactions taken together with the mutant cdc24 phenotype present the exciting possibility that this gene may have a functional significance in the development of diseases of genome stability. cdc24+ is a critical gene to characterize further because it encodes a novel protein that is essential for viability and clearly interacts genetically with conserved genes required for S phase progression.

Kang, Ho-Young, Eunjoo Choi, Sung-Ho Bae, Kyoung-Hwa Lee, Byung-Soo Gim, Hee-Dai Kim, Chankyu Park, Stuart A. MacNeill, and Yeon-Soo Seo. “Genetic Analyses of Schizosaccharomyces pombe dna2+ Reveal That Dna2 Plays an Essential Role in Okazaki Fragment Metabolism.” Genetics 155, no. 3 (July 1, 2000): 1055-1067. https://www.genetics.org/content/155/3/1055

Nasmyth, Kim, and Paul Nurse. “Cell Division Cycle Mutants Altered in DNA Replication and Mitosis in the Fission Yeast Schizosaccharomyces pombe.” Molecular and General Genetics MGG 182, no. 1 (May 1, 1981): 119–24. https://doi.org/10.1007/BF00422777

Gould, Kathleen L., C. Geoffrey Burns, Anna Feoktistova, Ching-Pei Hu, Sally G. Pasion, and Susan L. Forsburg. “Fission Yeast cdc24+ Encodes a Novel Replication Factor Required for Chromosome Integrity.” Genetics 149, no. 3 (July 1, 1998): 1221-1233. https://www.genetics.org/content/149/3/1221.long

Tanaka, Hiroyuki, Koichi Tanaka, Hiroshi Murakami, and Hiroto Okayama. “Fission Yeast Cdc24 Is a Replication Factor C- and Proliferating Cell Nuclear Antigen-Interacting Factor Essential for S-Phase Completion.” Molecular and Cellular Biology 19, no. 2 (February 1, 1999): 1038. https://doi.org/10.1128/MCB.19.2.1038.

Complete bibiliography available here: https://www.ncbi.nlm.nih.gov/myncbi/1T5QE0LNedh5h/bibliography/public/

Additional links:

Pasion Lab Members 

Policy on letters of recommendation

Teaching

Fall 2025

Teaching Mode: In-person, with co-instructor Dr. Kimberly Tanner

Biol 100 Human Biology 

Section 5  [Mon  Wed Fri, 10am - 10:50am, SEC 116] 

Section 7  [Mon  Wed Fri, 1pm - 1:50pm, SEC 116] 

Section 6  [Mon  Wed Fri, 4pm - 4:50pm, SEC 116] 

The course is intended for non-majors. Biol 100 meets the General Education B2: Life Science / 5B: Biological Science requirement.

All students who wish to enroll in Biol 100 (whether they are currently registered or wish to add the class) must attend the first day of class (MONDAY, August 25, 2025).

 

Pasion Lab Members

Fall 2025

PI: Sally Pasion

Graduate Students

Amy Tran

 

Previous Lab Members:

Vanessa Aguilera  (B.S. SF State, M.S. SF State, MBA Babson Graduate School, Semler Scientific)

Masae Ahmann (SF State graduate student)

Janis L Allen  (B.S. SF State, Principal Bioanalytical Project Manager Genentech)

Mattelin Bautista (Bridges Summer Student)

Dennis Bua (M.S. SF State, Ph.D. and postdoc Stanford, Bio-protocol, Stanford University School of Medicine)

Berenice Cabrera (B.S. and MS, SF State; Biology Instructor Foothill College, Ph.D. student at University of Michigan)

Alyn Castellanos (SF State graduate student, Roche)

Joni Castro (SF State graduate student, ADC Therapeutics, Genentech)

Jessica Chan (B.S. SF State; currently graduate student at USF,  Associate Lab Manager PrognomiQ Inc.)

Shani Chapman (M.S. SF State)

Layla Chirar (B.S. SF State; currently SF State graduate student)

Johnny Chavez (M.S. SF State)

Laura Cochrane (Research Technician, SF State graduate student)

Sheire Coleman (B.S. SF State, Educator)

Noel Cruz-Pacheco (M.S. SF State, currently Research Associate at UCSF)

Amy Dhirapong (graduate student, Ph.D. UC Davis, Genentech Pharmaceutical Specialist)

Letizia Diamante (Visiting International Scholar; MS, Univ. of Pavia; Ph.D. University of Cambridge, Science communicator and children's book writer )

Gemma Estrada Girona (M.S. SF State, Research scientist EMBL, Sainsbury Wellcome Centre for Neural Circuits and Behaviour, MeiraGTx Senior Research Scientist, Principal Scientist SpliceBio)

Gabriela Flores - (B.S. SF State, DPT MGH Institute of Health Professions, Physical Therapist)

Janell Garcia (B.S. SF State)

Gabriel Getchell - (B.S. SF State, Astellas Gene Therapies)

Brenna Gibson Tirumalashetty (B.S. and M.S. SF State, Climate Corporation Software Engineer)

Kadra Gulaid (B.S. SF State, MPH UC Berkeley)

Marwa Hararah (B.S. SF State)

Mela Hardin (M.A. in Mathematics, SF State, currently Ph.D. student at Arizona State)

Ngoc Hoang (B.S. and M.S. SF State; Adicet, Bio)

Logan Holbrook (currently SF State undergraduate student)

Sally Hutchinson (B.S. SF State)

Ugochi Ikeme (B.S. SF State, California Department of Fish and Wildlife)

Himanshi Jaswal (B.S. SF State)

Ryan Kendle (graduate student, M.D.-Ph.D. Drexel University, UCLA, oncologist)

Viivi Koivu (Visiting student, BS and MS, University of Turku, Blueprint Genetics )

Lorl Lee (Project SEED intern)

Philbert Lee (high school student intern, B.S. UCSC, M.S. SF State, Ph.D. University of Chicago, Molecular Biosciences)

Jiayu Luo (M.S. SF State, currently employed at Gene Editing company in Hong Kong)

Lisa Liang (Project SEED intern, B.S. Environmental Toxicology, UC Davis)

Alice Liu (high school student intern)

Anthony Xavier Lopez (B.S. SF State, M.S. SF State, currently Biology Professor at Mt San Antonio College)

Eduardo Lujan (B.S. SF State, M.S. SF State, currently Ph.D. student at UC Berkeley)

Nghiep Ly (B.S. SF State, M.S. SF State, Complete Genomics, BGI of America)

Elizabeth Mazza (B.S. SF State)

Jennifer Menjivar (B.S. SF State, MD David Geffen School of Medicine at UCLA, Resident at UCSF, pediatrician )

Mehnaz Malek (graduate student, currently at Bristol Myers Squibb)

Garima Mital (M.S. SF State, currently at Genentech)

Ariff Moolla (B.A. in Mathematics, B.S. in Cell & Molecular Biology SF State,  DO Touro University, pediatrician)

Bichloan Nguyen (B.S. and M.S. SF State)

Jose Valentin Ordonez (B.S. SF State)

Erica Pederson  (Research Technician, Research Associate at UC Berkeley)

J. Michelle Pierce (Bridges Summer student, B.S. Arizona State, SF Department of the Environment, Bay View Hunter's Point Community Advocates)

Justine Jenny Ramos (B.S. SF State, currently Ph.D. Student, UC Berkeley)

Terry Reyes (B.S. SF State, Ph.D. Stanford University, Genencor, Impossible Foods Inc. Regulatory Affairs, UPSIDE Foods Senior Manager Global Regulatory Affairs)

Nainoa Richardson (B.S. and M.S. SF State, Ph.D. University of Nice Sophia-Antipolis (UNS) Institute of Biology Valrose (iBV), postdoc at UCSF, Genentech Scientist 3)

Leonel Santibañez Vargas (Bridges Summer student, B.S. UC Riverside, Antibody Solutions)

Kanika Sethi (B.S. SF State, podiatry student at Samuel Merritt University)

Iqbal Thabet (SF State graduate student)

Marakee Tilahun (B.S. SF State)

Herlinda Tin (Bridges Summer student, B.A. in Psychology, UC Riverside; M.A. Massachusetts School of Professional Psychology, PsyD Clinical Psychology)

Anna Marie Tuazon (M.S. SF State, Ph.D. UC Davis; Gilead Sciences, Biogen Head of Strategy, Operations and Excellence)

Cherryl Valenzuela (Bridges Summer student)

Ntsaum Steve Vang (M.S. SF State, Medical School Student)

Laura Wazna-Blank (B.S. SF State)

Ivan Zamora (SF State graduate student, Impossible Foods Inc.)

 

updated 8/23/2024

Policy on Letters of Recommendation

Policy on Letters of Recommendation
This information is for students requesting a letter of recommendation from Dr. Pasion in the Department of Biology, SFSU.  This information does not reflect the official requirements for SFSU faculty.

It is essential that you allow sufficient time for preparing the letter, so you must contact me a minimum of ONE MONTH BEFORE the letter deadline.

•links about requesting letters of recommendation
•links for letter writers

If you are interested in obtaining a letter of recommendation, you must approach me with the following information:
1.    Complete name of school (or scholarship program) to which you are applying
2.    Complete mailing address for letter of recommendation (Most letters are submitted online, but for those letters that will be sent by regular US postal service, an addressed envelope with sufficient postage would be appreciated--see format for addressing the envelope here. Please do not put the stamp on the envelope, in case a new envelope is required)
3.    Form(s) to be sent with letter.  In some cases, the school/scholarship program has a form or template for submitting the letter of recommendation.  Many programs have online letter submission - please provide me with a list of all programs you are applying to with the application deadline.
4.    Signed form waiving your access to letter of recommendation.  The University provides this form

https://registrar.sfsu.edu/sites/default/files/documents/Letter%20of%20Recommendation%20Release%20Form.pdf

If you do not waive your right to access, the letter of recommendation is considered not confidential and may be discounted by evaluators at the recipient institution.  For online submissions, please provide me with a signed statement listing all schools that you WAIVE your right to access the letter. I will not write a letter of recommendation if you do not waive access to your letter.
5.    A copy of your unofficial SFSU transcript.
6.    A copy of your personal statement to be submitted to the school (or scholarship program).  I am looking for an explanation of your career goals or type of job or graduate school you hope to enter if this is not included in your  personal statement.
7.    Your contact information (address, day and night telephone numbers indicating acceptable contact hours, your e-mail address--in case I need additional information).  If you were a student in my class, please indicate the specific details (class, semester, and grade received)
8.    If you are using a campus letter writing service, provide all relevant information and forms.
9.    Specific deadlines for receipt of the letter (or when you will be picking up the letter if you need to send the letter with your application packet).
10.  You must meet with me to discuss aspects of your academic performance or other characteristics that will help strengthen your letter of recommendation.  Be aware that a letter for entry into a medical school or a graduate program will emphasize different aspects of your academic performance compared to a letter for a scholarship program.
REMEMBER that you should REMIND me (by e-mail, is fine) about the letter approximately one week before the deadline.

  • You should have all the information available in an electronic format (send by e-mail).
  • Even if I have written a letter for you before, it is a good idea to provide all of this information again (so that we do not lose time looking for the previous information)

Information for students who are requesting a letter of recommendation

Career Center-UC Berkeley Graduate School Letters of Recommendation
All about letters of recommendation
How to ask a Professor for a letter of recommendation

Recommendation letter etiquette

Information for people writing letters of recommendation
Ten tips for recommenders
Writing a letter of recommendation letter (HHMI)

Tips for writing strong letters of recommendation

Most letters of recommendation are submitted ONLINE. No stamp/envelopes required if the letters are submitted ONLINE. If the letter of recommendation is to be mailed  -- Format for addressed envelope (no stamp...Leave the return address blank):