1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Microarray expression profiles of 19 fluorescently sorted GFP-marked lines were analyzed (3–9, 23, 24). The colors associated with each marker line reflect the developmental stage and cell types sampled. Thirteen transverse sections were sampled along the root's longitudinal axis (red lines) (10). CC, companion cells. 16 (A) The majority of enriched GO terms (hierarchically clustered) are associated with individual cell types (blue bar). A smaller number are present across multiple cell types (green bar). (fig. S2) (B) GO category enrichment for hair cells confirms a previous report (15). Enriched cis-elements and an enriched TF family were also identified. (C) From the top 50% of varying probe sets, 51 dominant radial patterns were identified. Pattern expression values were mean-normalized (rows) and log2 transformed to yield relative expression indices for each marker line (columns). Marker line order is the same for all figures; see table S1 for marker line abbreviations. (D) Pattern expression peaks were found across one to five cell types. (E to G) Patterns where expression is enriched in single and multiple cell types support transcriptional regulation of auxin flux and synthesis. In all heat maps with probe sets, expression values were mean-normalized and log2 transformed. Expression is false-colored in representations of a root transverse section, a cut-away of a root tip, and in a lateral root primordium. (E) Auxin biosynthetic genes (CYP79B2, CYP79B3, SUPERROOT1, and SUPERROOT2) are transcriptionally enriched in the QC, lateral root primordia, pericycle, and phloem-pole pericycle (P = 1.99E–11, pattern 5). All AGI identifiers and TAIR descriptions are found in table S14. (F) Auxin amido-synthases GH3.6 and GH3.17 that play a role in auxin homeostasis show enriched expression in the columella, just below the predicted auxin biosynthetic center of the QC (P = 8.82E–4, pattern 13). (G) The expression of the auxin transporter, PINFORMED2, and auxin transport regulators (PINOID, WAG1) are enriched in the columella, hair cells, and cortex (P = 1.03E–4, pattern 31). 17 Schematic flowchart of the Human Protein Atlas. For each gene, a signature sequence (PrEST) is defined from the human genome sequence, and following RT‐PCR, cloning and production of recombinant protein fragments, subsequent immunization and affinity purification of antisera results inmunospecific antibodies. The produced antibodies are tested and validated in various immunoassays. Approved antibodies are used for protein profiling in cells (immunofluorescence) and tissues (immunohistochemistry) to generate the images and protein expression data that are presented in the Human Protein Atlas (Ponten et al., J Int Med, 2011). 18 19 20 21 22 23 24 25 26 27 Excample of an output of transcriptional profiling study using Illumina  sequencing performed in our lab. Shown is just a tiny fragment of the complete  list, copmprising about 7K genes revealing differential expression in the studied  mutant.  28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 In the figure, there is simplified scheme of vesicle trafficking pathways, regulated by GNOM and its closest relative, GNOM‐LIKE1 (GNL1). Secretory and membrane proteins are synthesised at the ER (blue) and passed onto the Golgi apparatus (green) by anterograde trafficking in COPII‐coated vesicles. The retrograde route from the Golgi apparatus to the ER is regulated by the ARF‐GEFs GNOM (GN) and GNL1, which regulate the recruitment of COPI coats to the Golgi membrane. On the secretory route, proteins are transported to the sorting station, the trans‐Golgi network (TGN; lilac). From there, proteins are either transported to the vacuole (grey) via multivesicular bodies (MVB, also called prevacuolar compartment, PVC, which corresponds to the late endosome; deep blue) or trafficked to the plasma membrane (PM). Plasma membrane proteins like the auxin efflux carrier PIN1 (red), which accumulates at the basal PM at steady state, are continually internalised and trafficked to the TGN, which resembles the early endosome (EE) in plants. From the TGN, PIN1 is recycled to the plasma membrane via the recycling endosome (RE; light blue). This pathway is regulated by the ARF‐GEF GNOM. 44 45 46 47 48