Cofilin-2, a novel type of cofilin, is expressed specifically at aggregation stage of Dictyostelium discoideum development

Aizawa, H Kishi, Y Iida, K Sameshima, M Yahara, I

H. Aizawa et al., Cofilin-2, a novel type of cofilin, is expressed specifically at aggregation stage of Dictyostelium discoideum development, GENES CELLS, 6(10), 2001, pp. 913-921

36

INGLESE

Article

Molecular Biology & Genetics

GENES TO CELLS

1356-9597 → ACNP

6

10

2001

913 - 921

ISI

1356-9597(200110)6:10<913:CANTOC>2.0.ZU;2-6

Background: A conventional cofilin, cofilin-1 in Dictyostelium discoideum p lays significant roles in cell proliferation, phagocytosis, chemotactic mov ement and macropinocytosis. Results: We identified a new member of the cofilin family, named cofilin-2 in D. discoideum. Cofilin-2 shows significant homology to a conventional Di ctyostelium cofilin, cofilin-1, through its entire sequence, and contains r esidues conserved among the cofilin family that are responsible for actin-b inding. On the other hand, several residues that are conserved among the co filin family are missing from cofilin-2. Purified cofilin-2 depolymerized a ctin filaments in a dose-and pH-dependent manner and reduced the apparent v iscosity of an actin solution, although they did not co-sediment with actin filaments at all. Cofilin-2 was not expressed in vegetative cells, but was transiently induced during the aggregation stage of development, whereas c ofilin-1 was predominantly expressed in vegetative cells. Immunocytochemist ry revealed that cofilin-2 localizes at substrate adhesion sites, where cof ilin-1 is almost completely excluded. Disruption of the cofilin-2 gene caus ed an increase in actin accumulation at the substrate adhesion sites. We al so found that cofilin-2 did not rescue Delta cof1 yeast cells, whereas cofi lin-1 did. Conclusions: Cofilin-2 may play a distinct role from that of cofilin-1 in d estabilization of the actin cytoskeleton during Dictyostelium development.