Cytoskeletal Dynamics

Research Interests:
The interest of our team lies in understanding the dynamics of acto-myosin contractile networks. We are particularly interested in the contractile ring, which functions during cytokinesis to partition the contents of the mother cell to the two daughter cells. The contractile ring assembles around the cell equator beneath the plasma membrane after the replicated chromosomes have segregated. Constriction of the ring progressively draws the plasma membrane inwards, closing the gap between the two daughter cells. We aim to learn about the rapid remodeling of this continuously changing structure, its dynamics and molecular architecture. Gaining mechanistic insight into cytokinesis is of significance for the understanding of tumorigenesis as failure of cytokinesis gives rise to polyploid cells, which have been postulated to be critical intermediates in the development of cancer. In addition, lessons learned about the contractile ring in cytokinesis will likely translate to other essential cellular processes that also utilize contractile networks composed of actin and myosin II, such as muscle contraction, tissue morphogenesis, cell migration, cell invasion and wound healing.

 

Figure Legend: A C. elegans one-cell embryo undergoing cytokinesis. Shown in red is the plasma membrane and in green non-muscle myosin II heavy chain, which localizes in the contractile ring at the tip of the cleavage furrow.

 

Research Projects:
In our lab, we use the nematode C. elegans as experimental system and a combination of cell biological and biochemical approaches. Actin, non-muscle myosin II and most of their regulators are well conserved in C. elegans and a variety of cellular contexts that involve actomyosin contractility are experimentally accessible in this system. These include polar body extrusion during meiosis, cytokinesis, polarity establishment, embryonic and tissue morphogenesis, muscle contraction, and neuronal development. Our favorite experimental approaches include live cell confocal microscopy for the development of image-based quantitative assays, molecular replacement technology for generation of transgenic worms and structure-function studies, and genetics. Our current projects focus on understanding the mechanisms that power contractile ring constriction and dictate its rate. We are also studying the roles of branched versus non-branched actin filaments during cytokinesis, the molecular organization of the constricting ring and the dynamics of the material within the ring during constriction.

 

References:
Carvalho A, Olson S, Gutierrez E, Zhang K, Noble L, Zanin E, Desai A, Groisman A and Oegema K. “Acute drug treatment in the early C. elegans embryo”. PLoS ONE. 2011. 6(9): e24656
Lewellyn L, Carvalho A, Desai A, Maddox A, Oegema K. “The chromosomal passenger complex and centralspindlin independently contribute to contractile ring assembly”. JCB. 2011.193(1): 155-69
Carvalho A, Desai A, Oegema K. “Structural memory in the contractile ring makes the duration of cytokinesis independent of cell size”. Cell. 2009. 137: 926-37
Yue Z*, Carvalho A*, Xu Z, Yuan X, Cardinale S, Ribeiro S, Lai F, Ogawa H, Gudmundsdottir E,Gassmann R, Morrison CG, Ruchaud S, Earnshaw WC. “Deconstructing Survivin: comprehensive genetic analysis of Survivin function by conditional knockout in a vertebrate cell line”. JCB. 2008; 183: 279-96. *authors contributed equally

 

Group Leader
822.jpeg
anacarvalho@ibmc.up.pt
People
Researchers

Chan, Elaine
fung.chan@ibmc.up.pt

Marta Franco da Silva, Ana
amsilva@ibmc.up.pt

Sampaio Osório, Daniel
daniel.osorio@ibmc.up.pt

Phd Students

Costa Santos, Inês
ines.santos@ibmc.up.pt

Leite, Joana
joana.leite@i3s.up.pt

Saramago, Joana
joana.saramago@ibmc.up.pt

Sobral, Ana Filipa
ana.sobral@i3s.up.pt

MSc Students

Pereira, Jaime
jaime.pereira@ibmc.up.pt

Trainees

Mendes, Adriana
adriana.mendes@i3s.up.pt

Technicians

Dias, Alexandra
alexandra.dias@i3s.up.pt


Home | Site Map | Contacts | Credits | Privacy & Cookies | Intranet | Social Networks |


rua alfredo allen, 208, 4200-135 porto - portugal | tel +351 220 408 800 | email: info@ibmc.up.pt | © copyright 2010 ibmc