Table 2.

Plasmids constructed in this study

Plasmid name	Construction
pKA50	pRS313 (CEN, HIS3) was cut with PvuII and religated to remove polylinker.
pKA51	SLA1 on Sal I fragment was blunt-ended using Klenow and ligated into pKA50 at the Pvu II site.
pKA53	pKA51 was cut with Eco RI removing a 1182-bp fragment and religated.
pKA54	PCR was used to generate an Apa I site at base 9 of the SLA1 coding sequence in pKA51. The plasmid was then cut with Apa I releasing a 575-bp fragment encompassing the first two SH3 domains.
pKA55	PCR was used to generate a Bam HI site at base 1522 of the SLA1 coding sequence in pKA51. The plasmid was then cut with Bam HI releasing a 1495-bp fragment encompassing the central “gap2” region.
pKA13	pKA51 was cut with Bam HI and Eag I, blunt-ended, and religated releasing a 754-bp fragment encoding most of the C-terminal repeat region.
pKA116	Xho I sites were generated by in vitro mutagenesis on either side of the third SH3 domain in pKA51. This domain was then excised, and the plasmid was religated.
pKA128	In vitro mutagenesis was used to mutate the coding sequence for the proline helix motif to give a change of P to S at residue 626.
pKA129	Xho I sites were generated by in vitro mutagenesis on the 5′ side of the coding region for the third SH3 domain and on the 3′ side of the second SH3 domain in pKA51. This Gap1 domain was then excised, and the plasmid was religated giving Sla1-Δgap1.
pKA130	Xho I sites were generated by in vitro mutagenesis on either side of the third SH3 domain in pKA54. This domain was then excised, and the plasmid was religated giving Sla1-Δall SH3.
pKA32	The DNA coding for the mutant Sla1-ΔG1+SH3#3 was excised from pKA53 using Xba I and cloned into pRS316 (CEN, URA3).
pKA139	S. pombe cosmid SPAC16E8 was cut with Eco RI and Hpa I, and the relevant fragment was cloned into pRS423 (2μ, HIS3).