“…These genes were selected solely on the basis of their leptokurtic association with guard cells, coupled with listed availability of two T-DNA insertional mutant lines. For six of these genes (At1g20880, At1g31335, At1g65020, At3g51760, At4g01880, and At5g35320), we could not verify two independent mutant lines lacking full-length transcripts, so we focused our efforts on the remaining four genes ( Figure 6): At1g50400, a putative mitochondrial import receptor subunit TOM40 homolog 2; At2g21080, annotated as a plant-specific unknown protein; At1g11100, an SNF2 domain-containing and helical domain containing protein; and At5g60410 (SAP and MIZ SUMO E3 ligase [SIZ1]) (Miura et al, 2009). None of these four genes had been previously reported to function in guard cells.…”