Conventional actins play a role in nearly all cellular processes, but many organisms also contain divergent actins with some degree of sequence variance. The unicellular green alga, Chlamydomonas reinhardtii contains two actin genes: IDA5, a conventional actin that is 89% homologous to rabbit skeletal muscle actin; and NAP1,a divergent actin with only about 65% homology to conventional actin. In my work, I'm seeking to identify the distinct functions of these two actins through biochemical approaches, as well as in the Chlamydomonas ​cell.  Specifically, I'm looking at the Arp2/3 complex, an actin nucleator composed of seven distinct subunits, and how it interacts with both IDA5 and NAP1 to perform cellular functions including ciliary assembly and maintenance and endocytosis.

Publications

Zhang, N.; Pazouki, L.; Nguyen, H.; Jacobshagen, S.; Bigge, B.M.; Xia, M.; Mattoon, E.M.; Klebanovych, A.; Sorkin, M.; Nusinow, D.A.; Avasthi, P.; Czymmek, K.J.; Zhang, R. "Comparative Phenotyping of Two Commonly Used Chlamydomonas reinhardtii Background Strains: CC-1690 (21gr) and CC-5325 (The CLiP Mutant Library Background)." Plants 2022, 11, 585. https://doi.org/10.3390/plants11050585

Bigge, B.M., Rosenthal, N.E., Sept, D., Schroeder, C.M., Avasthi, P. “Initial ciliary assembly in Chlamydomonas requires Arp2/3-dependent recruitment from a ciliary protein reservoir in the plasma membrane.” BioRxiv. 2021. doi.org/10.1101/2020.11.24.396002.

Craig, E. W., Mueller, D. M., Bigge, B. M., Schaffer, M., Engel, B.D., Avasthi, P. (2019). "The elusive actin cytoskeleton of a green alga expressing both conventional and divergent actins." Mol Biol Cell: mbc.E19-03-0141.

Conferences

Graduate:
  • Bigge, B.M., Avasthi, P. “An Arp2/3 complex and endocytosis-dependent mechanism for lithium-induced ciliary elongation.” Dartmouth College Molecular and Cell Biology Recruitment 2022. December 2021. Virtual. (Poster). 
  • Bigge, B.M., Avasthi, P. “An Arp2/3 complex and endocytosis-dependent mechanism for lithium-induced ciliary elongation.” Cell Bio 2021. December 2021. Virtual. (Poster).
  • Bigge, B.M., Avasthi, P. “Arp2/3-dependent actin networks in ciliary protein delivery in Chlamydomonas.” Cell Bio 2021. December 2021. Virtual. (Poster). 
  • Bigge, B.M., Avasthi, P. “Arp2/3-dependent actin networks in ciliary protein delivery in Chlamydomonas.” Triangle Cytoskeleton Meeting. September 2021. Virtual. (Poster). Award for top poster.
  • Bigge, B.M., Avasthi, P. “Arp2/3-dependent actin networks in ciliary protein delivery in Chlamydomonas.” Dartmouth College Molecular and Cell Biology Annual Retreat. August 2021. (Poster). 
  • Bigge, B.M., Avasthi, P. “Arp2/3-dependent actin networks in ciliary protein delivery in Chlamydomonas.” Dartmouth College Molecular and Cell Biology Research in Progress Seminar. April 2021. Virtual. (Oral Presentation). 
  • Bigge, B.M., Avasthi, P. “Novel roles for Arp2/3-mediated actin networks in ciliary assembly and in endocytosis-dependent gamete activation in Chlamydomonas.” Dartmouth College Molecular and Cell Biology Recruitment. April 2021. Virtual. (Poster). 
  • Bigge, B.M. “Arp2/3-dependent actin networks in ciliary protein delivery in Chlamydomonas.” BSCB GenSoc UK Cilia Network e-Symposium. January 2021. Virtual. (Oral Presentation).
  • Bigge, B.M., Avasthi, P. “Internalization Of Membrane Adhesion Proteins During Mating In Chlamydomonas Occurs Through Actin And Arp2/3 Dependent Endocytic Mechanisms” Cell Bio 2020. December 2020. Virtual. (Poster).
  • Bigge, B.M., Avasthi, P. “Arp2/3 Nucleated Actin Networks Are Required For Ciliary Assembly In Chlamydomonas” Cell Bio 2020. December 2020. Virtual. (Poster).
  • Bigge, B.M., Sept, D., Schroeder, C.M., Avasthi, P. “Conventional and divergent actin networks mediated by Arp2/3 in endocytosis, higher order actin structures, and cilia in Chlamydomonas” Dartmouth College Molecular and Cell Biology Retreat. August 2020. Virtual. (Poster). Award for being in the Top 3 posters.
  • Bigge, B.M., Sept, D., Schroeder, C., Avasthi, P. ​"Arp2/3 nucleates conventional and divergent actin networks in Chlamydomonas Reinhardtii" Stowers Developmental Cell Biology Conference. April 2020. Kansas City, MO. (Poster, Cancelled due to COVID-19)
  • Bigge, B.M., Sept, D., Schroeder, C., Avasthi, P. ​"Arp2/3 nucleates conventional and divergent actin networks in Chlamydomonas Reinhardtii" KUMC Student Research Forum (SRF). March 2020. Kansas City, KS. (Oral Presentation, Cancelled due to COVID-19)
  • Bigge, B.M., Sept, D., Schroeder, C., Avasthi, P. ​"Arp2/3 nucleates conventional and divergent actin networks in Chlamydomonas Reinhardtii" Chicago Cytoskeleton Meeting. March 2020. Chicago, IL. (Poster, Cancelled due to COVID-19)
  • Bigge, B.M., Avasthi, P. ​"​Arp2/3-mediated branched actin networks play a role in ciliary assembly and maintenance in Chlamydomonas" American Society of Cell Biology (ASCB). December 2019. Washington D.C. (Oral Presentation)
  • Bigge, B.M., Sept, D., Schroeder, C., Avasthi, P. ​"Arp2/3 nucleates conventional and divergent actin networks in Chlamydomonas Reinhardtii" American Society of Cell Biology (ASCB). December 2019. Washington D.C. (Poster)
  • Turkowitch, D., Bigge, B.M., Craig, E.W., Avasthi, P. ​"​Assembly of Divergent Actin Rings in Chlamyodonas is both formin and arp2/3 dependent but myosin indepent." American Society of Cell Biology (ASCB). December 2019. Washington D.C. (Poster)
  • Salberg, A., Bigge, B.M., Craig, E. W., Avasthi, P. ​"​Novel actin ring structure in vegetative Chlamydomonas cells plays a potential role in nuclear integrity." American Society of Cell Biology (ASCB). December 2019. Washington D.C. (Poster)
  • Bigge, B.M., Sept, D., Avasthi, P. "​Arp2/3 can nucleate filaments of a divergent actin with few conserved Arp2/3 binding residues"  KUMC Student Research Forum (SRF). March 2019. Kansas City, KS. (Oral Presentation)
  • Bigge, B.M., Sept, D., Avasthi, P. "​Arp2/3 can nucleate filaments of a divergent actin with few conserved Arp2/3 binding residues"  American Society of Cell Biology (ASCB). December 2018. San Diego, CA. (Poster)

Undergraduate:
  • Bigge, B.M., Kadarla, K., Beck, M.R. "Myopalladin's Role in Cardiac Muscle Function and Disease" Kansas Idea Network of Biomedical Research Excellence (K-INBRE) Symposium. January 2017. Manhattan, KS. (Poster) 
  • Bigge, B.M., Kadarla, K., Beck, M.R. "Myopalladin's Role in Cardiac Muscle Function and Disease" Undergraduate Research and Creative Activity Forum (URCAF). 2017. Wichita, KS. (Poster)