TABLE 1.

Summary of genetic and biochemical effects of ARC35 alleles

++, wild type phenotype. +, slightly impaired phenotype. −, strongly impaired phenotype. “Clumps” indicates aberrantly large actin formation (see text). NA, not applicable. ND, not determined. “No NPF” actin nucleation activity data were taken from Fig. 4C. Polarized actin patches were scored after Alexa 488-phalloidin staining cells (representative images in Fig. 6) as the percentages of budded cells with six or more patches in the mother (n > 100 cells). The endocytosis data are from Fig. 7B.

Allele	Mutations	Cell growth		Actin nucleation activity		Cells with polarized actin patches		Endocytosis
		25 °C	37 °C	No NPF	+WASp	25 °C	37 °C
				%	%	%	%	%
ARC35		++	++	100	100 ± 3.1a	85	36	92
arc35-101	D50A, K51A	++	++	83	75 ± 7.8a	28	12	10
arc35-102	K79A	++	+	50	78 ± 5.7a	47	11	29
arc35-103	R173A, D174A, E175A	++	++	94	92 ± 15.4a	74	19	79
arc35-104	D185A, R186A	++	−	13	45 ± 8b	15	1	6
arc35-105	K205A, V206A, Q209A	−	−	ND	40 ± 2.7b	NA	NA	NA
arc35-106	D213A, R251A, K216A, R217A	−	−	ND	14 ± 0.5b	NA	NA	NA
arc35-107	H231A, E232A	++	++	167	97 ± 23.2a	85	28	69
arc35-108	L235A, E236A, K238A	++	−	13	37 ± 4.5b	8	0	8
arc35-109	F259A, R261A	++	−	2	33 ± 5.9b	2	0	8
arc35-110	L228K	++	++	28	77 ± 11.1b	18	2	27
arc35-111	K61A	++	++	76	70 ± 7.0a	81	14	73
arc35-112	K307A, K310A, R311A	+	−	2	19 ± 3.9b	4 (clumps)	1 (clumps)	10
arc35-113	R297A, R299A, R301A	++	++	49	74 ± 1.7a	75	18	69
arc35-114	S223A, Q226A	++	++	ND	62 ± 6.6a	ND	ND	ND

^aThis WASp-dependent actin nucleation activity was taken from Fig. 3B.

^bThis WASp-dependent actin nucleation activity was taken from Fig. 5C.