1. Glutamyl-tRNA 5-Aminolevulinic acid Protoporphyrinogen IX Mg-Proto IX Heme Mg-Proto IX ME HEMA GSA PPO FC PORB CHLD, CHLH, CHLI Glutamate 1-semialdehyde ALAD Pchlide Chlorophyll Proto IX ALA Fig. S1. The tetrapyrrole pathway in plants showing intermediates and genes analyzed in this study. Intermediates: Proto IX, protoporphyrin IX; Mg-Proto IX, Mg-protoporphyrin IX; Mg-Proto IX ME, Mg-protoporphyrin IX methyl ester; Pchlide, protochlorophyllide. Genes and enzymes that correspond to the gene names: HEMA, glutamyl-tRNA reductase; GSA, glutamate 1-semialdehyde aminotransferase; ALAD, ALA dehydratase; PPO, protoporphyrinogen oxidase; FC, ferrochelatase; CHLD, D-subunit of Mg-chelatase; CHLH, H-subunit of Mg-chelatase; CHLI, I-subunit of Mg-chelatase; PORB, protochlorophyllide oxidoreductase B. Supplemental Data

2. Signal transduction mechanisms Posttranslational modification Intracellular trafficking Translation and ribosome Transcription Carbohydrate metabolism RNA processing Lipid metabolism Amino acid metabolism Secondary metabolism Replication and repair Cytoskeleton Inorganic ion metabolism Chromatin Cell cycle Cell wall Nucleotide metabolism Nuclear structure Coenzyme metabolism Extracellular structure Defence mechanisms Energy production and conversion Number of differentially expressed genes by ALA Fig. S2. COG classes of the proteins encoded by the differentially expressed genes in response to exogenous ALA. In each functional category, the genes are grouped according to their regulation by ALA treatment (> 1.6-fold change). Red bars show ALA- induced genes and cyan bars ALA-repressed genes.

3. Transcription factor Translation initiation Proteasome Elongation factor Ribosome RNA polymerase Ribosome RNA binding Transcription factor Cell cycle rRNA processing Signal transduction Fig. S3. Network of a significantly (P ≤ 0.05) altered genes in ALA-treated rice plants. Genes in network are the corresponding Arabidopsis homologues of differentially expressed rice genes in microarray analysis. Each node in this network represents differentially expressed genes. The red and blue nodes correspond to the up-regulated and down-regulated states, respectively, according to the relative gene-expression levels between control and ALA-treated rice plants. The lines between these nodes represent the protein-protein interactions.

4. Relative mRNA level Os07g0545400 Os10g0396300 Os01g0888700 Os11g0700500 Os03g0803900 Os01g0607800 Os01g0179600 Os07g0656800 Fig. S4. Validation of microarray results with the expression profiles of eight genes in the ALA-treated rice plants as detected by qRT-PCR. The plants were subjected to the same treatments as in Fig. 2. Treatment notations are the same as in Fig. 2. Total RNAs were purified from plants and reverse transcribed. The resultant cDNAs were used as templates for qRT-PCR using Actin as an internal control. The Cont-6 was used for normalization, with the expression level of the sample set to 1. Error bars represent SE, and representative data from three independent experiments are presented.