Schematic diagram of chimeric selectable marker plasmids and non-selectable, co-transformed plasmids. Plasmids pPmr3 (A) and paphG (B) are selectable plasmids, and plasmids ptubar4 (C), pHsp-HA (D), pPsaD-GLuc (E), and pHsp70A-GLuc (F) are non-selectable, co-transformed plasmids. Introns in (B-D) and (F) are indicated by right-angled lines. The hsp70A gene in (D) was tagged with a sequence coding for the HA-epitope (little flag). All constructs are within pBluescript II (pBS) or pUC18 vectors. The positions of DNA fragments that were amplified by genomic PCR (gPCR) or RT-PCR are indicated. Positions of probes that were used in Southern blots are indicated (probe). The plasmids are described in detail in the Methods section. V.c., Volvox carteri; C.r., Chlamydomonas reinhardtii; S.r., Streptomyces rimosus; G.p., Gaussia princeps; ars, arylsulfatase gene; β-tub, β2-tubulin promoter; luc, luciferase gene.