Introduction Cells maintain their biological activities by importing and exporting various substances. Provision of energy and nutrients and efflux of salts, biochemicals, and ions are necessary to maintaining biological activity in prokaryotic and eukaryotic cells. Environmental situations within cells differ among organisms: unicellular organisms cannot control the ion concentrations outside the cell, but multicellular eukaryotes (especially animals) can precisely regulate the ion concentrations of their cellular environments within micromolar ranges. Therefore, we can expect organisms to differ in gene number, structure, and function according to their biological abilities and environmental situations. Recent sequence analyses of entire genomes have made it possible to confirm the existence of homologous genes by computer data analysis. It is also possible to reveal the overall patterns of gene networks. In plants, complete genomic sequences are available for Arabidopsis and rice, but gene annotation programs are not yet sufficiently accurate to determine the function of all genes Instead, full-length cDNA data are useful for precise analysis of genes. Because transport activities are required at distinct levels in most tissues, we expected that the transcripts of most transmembrane transporters would be represented in full-length cDNA libraries from plants at various developmental stages, various plant tissues, and plants exposed to various treatments. 2003 2007 2000 2002 2005 http://mips.gsf.de/proj/plant/jsf/ 2004 2003 http://rapdb.lab.nig.ac.jp/ 2007 2008 http://www.tigr.org/tdb/e2k1/osa1/index.shtml 2007 1998 1999 2001 2001 2005 http://www.genenames.org/cgi-bin/hgnc_search.pl 2004 http://www.membranetransport.org/index.html 2004 http://plantst.genomics.purdue.edu/ 2003 http://aramemnon.botanik.uni-koeln.de/ 2003 General comparisons of membrane transport genes 3 7 8 2 4 Escherichia coli Arabidopsis thaliana Oryza sativa Caenorhabditis elegans Drosophila melanogaster Homo sapiens Neurospora crassa Saccharomyces cerevisiae E. coli 2 2003 2 2 2 1 1 Fig. 1 Numbers of membrane transporter proteins of each class Escherichia coli Arabidopsis thaliana Oryza sativa Caenorhabditis elegans Drosophila melanogaster Homo sapiens Neurospora crassa Saccharomyces cerevisiae  Table 1 Comparative analysis of membrane transporter gene in many organisms Gene family E. coli K12 A. thaliana O. sativa C. elegans D. melanogaster H. sapiens  N. crassa 74 S. cerevisiae  Material Present in Energy-dependent (pump) ABC  67 110 153 48 51 47 31 24 Various All ArsAB  0 0 1 0 1 1 1 1 Anion All F-ATPase (catalytic)  1 5 6 2 1 2 2 2 + + All H+-PPase  0 3 9 0 0 0 0 0 + P, a (vacuolar) IISP  0 3 5 0 1 3 2 9 Protein All MPT  0 6 14 1 18 14 8 18 Protein Eukaryote (mitochondria) P-ATPase  4 46 57 22 19 32 19 16 + + 2+ All Channel ACC 0 0 0 0 0 7 0 0 2+ A (neuron) Annexin  0 8 10 0 7 13 1 0 2+ Eukaryote Bcl-2  0 0 0 0 1 12 0 0 Anion A (mammal ) Bestrophin  0 0 0 21 4 4 0 0 − − CD20 0 0 0 0 0 9 0 0 2+ A (B-lymphocyte ) ClC  3 7 14 6 3 10 3 1 − All Connexin  0 0 0 0 0 18 0 0 Various A (vertebrate) CSC  0 2 1 0 0 0 0 0 Various P (chloroplast) CytB  0 19 7 0 10 13 1 9 + All E-ClC  0 4 4 0 0 4 0 0 − A (mammal), P (distant homolog) ENaC 0 0 0 20 25 8 0 0 + A (epithelial cell, brain) GIC  0 19 17 9 27 20 0 0 2+ + All Hsp70  0 17 23 0 14 14 4 0 Cation  All ICC 0 0 0 0 0 1 0 0 − A (mammal) ICln  0 1 2 1 0 1 0 0 − A, P (distant homolog) Innexin  0 0 0 22 8 0 0 0 Various A (invertebrate) IRK-C 0 0 0 1 3 22 0 0 + A, B LIC  0 0 0 69 23 45 0 0 Various A Mid1 0 0 0 0 0 0 0 1 2+ Y MIP 2 38 38 7 7 11 1 4 2 2 3 All MIT 2 0 0 0 0 0 2 3 2+ 2+ 2+ Y, a, B MscL  1 0 0 0 0 0 0 0 Various B MscS  6 8 7 0 0 0 0 0 Various P, B NSCC2  0 1 1 1 1 1 0 1 Cation A, Y, F O-ClC 0 0 0 0 1 6 0 0 − A PCC  0 0 0 0 5 6 0 0 + + 2+ A PLM 0 0 0 0 0 7 0 0 Anion A (mammal) RIR-CaC  0 0 0 5 3 6 0 0 2+ A Tic110 0 1 2 0 0 0 0 0 Various P TRP-CC  0 0 0 5 7 23 0 1 2+ A, Y,  UT 0 0 0 0 0 2 0 0 Urea A (vertebrate), B  VIC  1 35 18 63 31 90 2 2 + + 2+ All Phosphotransferase System (PTS) GPTS  6 0 0 0 0 0 0 0 Carbohydrate B SSPTS  23 0 0 0 0 0 0 0 Carbohydrate B Secondary Transporter AAA  0 2 3 0 0 0 0 0 ATP Plant (chloroplast) AAAP  0 43 77 11 15 13 4 7 Amino acid, Auxin A, P, F, Y AAE 1 0 0 0 0 0 0 0 Aspartate, Alanine  B AbgT 1 0 0 0 0 0 0 0 p-Aminobenzoyl-glutamate  B ACR3  0 0 0 0 0 0 1 1 Arsenite, Antimonite  Y, B AE  0 7 3 4 2 10 2 1 + 3 − + − 3 3 A, P, Y AEC  1 8 8 0 0 0 0 0 Auxin P, Y, B AGCS  1 0 0 0 0 0 0 0 Alanine, Glycine B, a Amt 1 6 13 6 2 4 4 3 3 2 All APC 22 12 14 11 11 14 15 24 Amino acid, Polyamine All ArsB  2 0 0 0 5 1 0 0 Arsenite, Antimonite  All (with distant homolog) BASS  1 5 6 0 2 5 0 1 Organic acid All BCCT  3 0 0 0 0 0 0 0 Betaine/Carnitine/Choline B, a BenE  1 0 0 0 0 0 0 0 Benzoate B CaCA  2 12 23 8 11 8 8 4 2+ All CCC  0 1 2 6 5 9 1 1 + + − All CDF  2 8 11 8 7 10 8 5 2+ 2+ All CHR 0 0 0 0 0 0 1 0 4 2− 4 2− F, B CNT 3 0 0 2 2 3 1 0 Nucleoside A, Y, B CPA1 2 8 7 11 5 3 3 2 + + All CPA2  3 32 16 0 0 1 2 1 + + All DAACS 3 0 0 6 2 7 0 0 Dicarboxylate, Amino acid A, B DASS  5 4 5 4 3 5 0 3 Various A, P, Y, B Dcu  2 0 0 0 0 0 0 0 C4-Dicarboxylate  − DcuC  2 0 0 0 0 0 0 0 C4-Dicarboxylate  − DMT  16 121 57 15 14 18 6 9 Various  All ENT  0 8 4 5 3 4 1 1 Nucleoside A, P, Y ESS  1 0 0 0 0 0 0 0 Glutamate B FBT  0 9 8 0 0 0 0 0 Folate, Biopterin P, B, a FNT  4 0 0 0 0 0 1 1 Formate, Nitrate Y, B, a GntP 7 0 0 0 0 0 0 0 Carbohydrate B (E. coli, Bacillus)  GPH  6 9 8 1 1 5 2 0 Sugar A, P, F, a, B GUP  0 0 1 0 0 0 1 2 Glycerol A, P, Y, F, B HAAAP  8 1 0 0 0 0 0 0 Amino acid B, P (distant homolog) KDGT  1 0 0 0 0 0 0 0 2-Keto-3-Deoxygluconate B KUP  1 13 21 0 0 0 1 0 + P, F, B LCT 0 0 0 0 2 2 1 1 Cystine A, P, F LctP 2 0 0 0 0 0 0 0 Lactate, Glycolate  B, a LIV-E 1 0 0 0 0 0 0 0 Amino acid (L,I,V) B, a LIVCS  1 0 0 0 0 0 0 0 Amino acid (L,I,V) B LysE  1 0 0 0 0 0 0 0 Lysine B MC  0 52 66 34 45 44 34 34 Various  Eukaryote MET  0 0 0 0 0 3 0 0 Nucleoside, etc. A MFS  70 90 145 137 144 82 141 85 Various  All MOP 8 56 48 0 0 2 1 3 Various (Drugs etc.,) All MTC  0 2 2 6 2 3 1 1 Various (Anionic substrate ) Eukaryote NCS1  2 1 0 0 0 0 3 10 Nucleobase, Thiamine  P, F, Y, B, a NCS2 11 12 11 5 1 4 1 0 Nucleobase,etc. All NhaA  1 0 0 0 0 0 0 0 + + Prokaryote NhaB 1 0 0 0 0 0 0 0 + + All NhaD  0 2 1 0 0 0 0 0 + + + P, B NiCoT  0 0 0 0 0 0 1 0 2+ 2+ All Nramp 1 7 10 2 1 2 2 3 2+ 2+ All NSS  0 0 0 12 21 18 0 0 Neurotransmitters etc., A OAT  0 2 2 3 8 11 0 0 Various A, P, F, Y OPT 0 15 34 0 0 0 4 3 Oligopeptide P, B, a OST  0 0 0 0 0 2 0 0 Organic compound  Eukaryote Oxa1 1 4 5 0 1 1 0 1 Protein All (with distant homolog) PiT 2 1 3 5 1 2 1 1 4 2− 4 2− All PnaS  1 0 0 1 0 2 0 0 Inorganic phosphate  A (mammal) POT  4 50 61 3 3 4 2 1 Oligopeptide All RFC  0 0 0 3 3 4 0 0 Folate, Tiamine A RhtB  5 0 0 0 0 0 0 0 Amino acid B, a RND  8 2 1 24 4 7 2 1 Various  All SSS  4 1 1 3 19 11 2 1 Various All SulP  1 11 15 7 9 11 4 4 4 2− All Tat  1 0 1 0 0 0 0 0 Protein − TDT  1 4 9 0 0 0 2 1 Tellurite, C4-Dicarboxylate  All (with distant homolog) ThrE  1 0 0 0 0 0 0 2 Threonine, Serine  All (with distant homolog) TRAP-T  1 0 0 0 0 0 0 0 Various B, a Trk  2 1 1 0 0 0 2 2 + P, Y, B ZIP  0 13 18 6 5 2 5 3 2+ 2+ All Unclassified Ctr1  0 0 0 0 0 0 0 1 Dipicolinic Acid  Y, B Ctr2  0 5 7 4 3 2 2 2 2+ All FeoB  1 0 0 0 0 0 0 0 2+ B, a FeT  0 0 0 0 0 0 0 1 2+ 2+ 2+ Y FP  0 0 0 0 0 1 0 0 2+ A (mammal) LPI  0 0 0 0 0 5 0 0 Protein A OFeT  1 0 0 0 0 0 1 2 2+ 3+ Y, B PnuC  1 0 0 0 0 0 0 0 Nicotinamide mononucleotide B PPI  0 0 0 0 6 6 3 0 Protein A, F, B PUP  1 15 4 0 0 0 0 0 Peptide, Fatty acid P, B Note − Energy (ATP, pyrophosphate)-dependent (pump) system 1 2 E. coli 2 1 2005 2002 2004 E. coli Fig. 2 Comparison of numbers of pump genes among various organisms Escherichia coli Arabidopsis thaliana Oryza sativa Caenorhabditis elegans Drosophila melanogaster Homo sapiens Neurospora crassa Saccharomyces cerevisiae + + + +  1 2 2001 2006 + + + 2+ 1 2 2001 2003 + 2+ 2+ + 2+ 2+ 2+ 2+ 2+ 2+ 2006 + + + + + + + + + + + + + 1 2 1999 2002 + + + Ion channel systems 1 3 − + Fig. 3 Comparison of numbers of channel genes among various organisms E. coli A. thaliana O. sativa C. elegans D. melanogaster H. sapiens N. crassa S. cerevisiae + + + + 2+ 2+ 2+  2+ + + 1 3 2000 2002 2003 2003 2003 + + + + + + 2 3 + + CytB MscS 1 3 Table 2 Comparison of the genome size, total and membrane transport gene numbers in many organisms  E. coli K12 A. thaliana O. sativa C. elegans D. melanogaster H. sapiens  N. crassa 74 S. cerevisiae  Genome Size (Mb) 4.6 125 430 97 120 3150 40 13 Total gene number 4,290  26,000  37,000  20,621  13,489  30,000  10,082  5,804  Total Transporter Proteins 354 984 1200 654 590 754 344 300 Transporters per Mb genome 76.74 7.82 2.84 6.75 4.3 0.24 8.63 25.38 Transporters per whole gene 0.082 0.038 0.033 0.033 0.044 0.025 0.034 0.052 ATP-dependent pumps 72 (20%) 173 (18%) 249 (21%) 72 (11%) 72 (12%) 82 (11%) 53 (15%) 43 (14%) Ion Channels 15 (4%) 131 (13%) 178 (15%) 229 (35%) 158 (27%) 322 (43%) 12 (3%) 24 (8%) Phosphotransferase Systems (PTS) 30 (8%) 0 0 0 0 0 0 0 Secondary Transporters 233 (66%) 658 (67%) 762 (63%) 349 (53%) 351 (59%) 336 (44%) 273 (79%) 227 (75%) Unclassified 3 (1%) 22 (2%) 11 (1%) 4 (1%) 9 (1%) 14 (2%) 6 (2%) 6 (2%) + + 2005 1 3 2002 2005 AQP SIP NIP TIP Phosphotransferase system (bacteria) 1 2 2005 Secondary transporter (transporter) system 1 2 4 Fig. 4 Comparison of numbers of secondary transport genes among organisms Escherichia coli Arabidopsis thaliana Oryza sativa Caenorhabditis elegans Drosophila melanogaster Homo sapiens Neurospora crassa Saccharomyces cerevisiae + + 2+ + + + + + 2+ + +  2+ 2+  1991 1998 1999 2000 2002 2003 1998 1999 2005 4 1998 2002 1999 1999 2001 2002 2002 + + 1999 2000 2000 1 2 4 1 2 4 + + 3 5 + + + + + + + + + 3 5 Table 3 Comparison of secondary transporter genes  E. coli  A. thaliana O. sativa C. elegans D. melanogaster H. sapiens  N. crassa  S. cerevisiae  Present in Material Cotransporter Direction AAA  0 2 3 0 0 0 0 0 P (chloroplast) ATP +  in (same) AAAP 0 43 77 11 15 13 4 7 A, P, F, Y Amino acid, Auxin +  in (same) AAE  1 0 0 0 0 0 0 0 B l-Aspartate, l-Alanine  each other both (anti) AbgT 1 0 0 0 0 0 0 0 B p-Aminobenzoyl-glutamate  +  in (same) ACR3 0 0 0 0 0 0 1 1 B, Y Arsenite, Antimonite  ? out AE  0 7 3 4 2 10 2 1 A, P, Y + 3 − + 3 3 + + − both (anti) AEC  1 8 8 0 0 0 2 4 P, Y, B Auxin +  out (anti) AGCS 1 0 0 0 0 0 0 0 a, B Alanine, Gycine + + in (same) Amt  1 6 13 6 2 4 4 3 All 3 2 ? both APC  22 12 14 11 11 14 15 24 All Amino acid, Polyamine + in (same) ArAE 3 11 9 0 0 0 0 0 P, Y, B, a Armate acid (Malate etc.,) ? out ArsB  2 0 0 0 5 1 0 0 All (with distant homolog) Arsenite, Antimonite  ? out BASS  1 5 6 0 2 5 0 1 All Organic acid + in (same) BCCT  3 0 0 0 0 0 0 0 B, a Betaine/Carnitine/Choline +  in (same) BenE  1 0 0 0 0 0 0 0 B Benzoate +  in (same) CaCA  2 12 23 8 11 8 8 4 All 2+ + + both (anti)  CCC  0 1 2 6 5 9 1 1 All + + − + + − both (same) CDF 2 8 11 8 7 10 8 5 All 2+ 2+ + + out (antit) CHR  0 0 0 0 0 0 1 0 F, B 4 2− 4 2− + both (anti) CNT 3 0 0 2 2 3 1 0 A, Y, B Nucleoside + + in (same) CPA1  2 8 7 11 5 3 3 2 All + + + + − both (anti) CPA2  3 32 16 0 0 1 2 1 All + + + out (anti) DAACS  3 0 0 6 2 7 0 0 A, B Dicarboxylate, Amino acid + + in (same) DASS 5 4 5 4 3 5 0 3 − Aminoacid, Sulfate, Phosphate etc., + + in (same), both (anti) Dcu 2 0 0 0 0 0 0 0 − C4-Dicarboxylate  Dicarboxylate both (anti) DcuC 2 0 0 0 0 0 0 0 − C4-Dicarboxylate + + DMT  16 121 57 15 14 18 6 9 All C3 Carbohydrate, Sugar, Nucleotide etc., + out (anti) ENT 0 8 4 5 3 4 1 1 A, P, Y Nucleoside ? both ESS  1 0 0 0 0 0 0 0 B Glutamate + in (same) FBT  0 9 8 0 0 0 0 0 P, a, B Folate, Biopterin +  in (same) FNT  4 0 0 0 0 0 1 1 Y, a, B Formate, Nitrate +  in (same) GntP  7 0 0 0 0 0 0 0 B (E. coli, Bacillus) Carbohydrate +  in (same) GPH 6 9 8 1 1 5 2 0 A, P, F, a, B Sugar + +  + in (same) GUP  0 0 1 0 0 0 1 2 A, P, F, Y, B Glycerol +  in (same) HAAAP  8 1 0 0 0 0 0 0 B, P (distant homolog) Amino acid +  in (same) KDGT  1 0 0 0 0 0 0 0 B 2-Keto-3-Deoxygluconate +  in (same) KUP  1 13 21 0 0 0 1 0 P, F, B + none in LCT 0 6 3 0 2 2 1 1 A, P, F Cystine +  in (same) LctP  2 0 0 0 0 0 0 0 a, B Lactate, Glycolate  +  in (same) LIV-E 1 0 0 0 0 0 0 0 a, B Amino acid (L, I, V) +  in (same) LIVCS 1 0 0 0 0 0 0 0 B Amino acid (L, I, V) + + in (same) LysE  1 0 0 0 0 0 0 0 B Lysine + − − =  + =  MC  0 52 66 34 45 44 34 34 Eukaryote C3 Carbohydrate, Sugar, Nucleotide etc., Various both (anti) MET 0 0 0 0 0 3 0 0 A Nucleoside, Hydrophobic compound  +  both (anti) MFS  71 92 145 134 136 81 141 85 All C3 Carbohydrate, Sugar etc., + + + + MOP (MATE)  8 56 48 0 0 2 1 3 All Various (Drugs, Polysaccharides etc.,) + + out (anti) MTC  0 2 2 6 2 3 1 1 Eukaryote Various (Anionic substrate ) +  in (same) NCS1 2 1 0 0 0 0 3 10 P, F, Y, a, B Nucleobase, Thiamine  +  in (same) NCS2  10 12 11 5 1 4 1 0 All Nucleobase, (Ascorbate = (mouse only))  + + in (same) NhaA  1 0 0 0 0 0 0 0 Prokaryote + + + + both (anti) NhaB  1 0 0 0 0 0 0 0 All + + + + both (anti) NhaD  0 2 1 0 0 0 0 0 P, B + + + + + + both (anti) NiCoT  0 2 0 0 0 0 1 0 All 2+ 2+ 2+ 2+ both (anti) Nramp  1 7 10 2 1 2 2 3 All 2+ 2+ 2+ 2+ 2+ 2+ i2+ 2+ +  in (same) NSS  0 0 0 12 21 18 0 0 A −  + in (same) OAT  0 2 2 6 8 11 0 0 A, P, F, Y Various Anion  both (anti) OPT  0 15 34 0 0 0 4 3 P, B, a Oligopeptide +  in (same) OST 0 0 0 0 0 2 0 0 Eukaryote Organic compound (mostly anions) each other both (anti) Oxa1  1 4 5 0 1 1 0 1 All (with distant homolog) Protein each other both (anti) PiT  2 1 3 5 1 2 1 1 All 4 2− 4 2− + + in (same) PNaS  1 0 0 1 0 2 0 0 A, B (distant homolog) Inorganic phosphate  + in (same) POT  4 50 61 3 3 4 2 1 All Oligopeptide +  both (same) RFC 0 0 0 3 3 4 0 0 A Folate, Tiamine + − both (anti) RhtB 5 0 0 0 0 0 0 0 a, B Amino acid +  out (anti) RND 8 2 1 24 4 7 2 1 All Heavy metals, Drugs, Lipids etc., +  out (anti) SSS 4 1 1 3 19 11 2 1 All Sugar, Amino acid, Organo cation, Anion + + in (same) SulP  1 11 15 7 9 11 4 4 All 4 2− +  in (same) Tat 1 0 1 0 0 0 0 0 − Protein none out TDT  1 4 9 0 0 0 2 1 All (with distant homolog) Tellurite, C4-Dicarboxylate  +  in (same) ThrE 1 0 0 0 0 0 0 2 All (with distant homolog) Threonine, Serine  +  both (anti). TRAP-T 1 0 0 0 0 0 0 0 a, B Various +  in (same) Trk  2 1 1 0 0 0 2 2 P, Y, B + +  in (same) ZIP  0 13 18 6 5 2 5 3 All 2+ 2+ none in Note − Direction: “in” , “out”, and “both” indicate transport direction of materials through cell membrane, and “same” means material and cotranspoter move to the same dirction, “anti” means the different directions Fig. 5 Comparison of co-transport molecules of secondary active transporters among various organisms Escherichia coli Arabidopsis thaliana, Oryza sativa, Caenorhabditis elegans, Drosophila melanogaster, Homo sapiens Neurospora crassa Saccharomyces cerevisiae  + 1998 1999 2001 2002 2006 + 1994 2001 2001 2004 + + 2001 2001 2003 2004 2004 2000 2003 2003 + \documentclass[12pt]{minimal}
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\begin{document}$$ {\text{SO}}^{{{\text{2}} - }}_{{\text{4}}} $$\end{document} + + + + + 3 5 1995 1996 1998 1998 1999 1999 2000 2001 2004 + + + + + + Comparative analysis of membrane transporter systems in Arabidopsis and rice 2 6 6 2+ + + 2+ Fig. 6 Comparison of membrane transport genes in Arabidopsis and rice + 2+ + 2+ 2+  2005 E. coli H. sapiens In the eight diverse organisms that we compared, the number of membrane transporter genes (300–1200) varied less than that of genes in other categories. The minimum number of genes indispensable to retaining cell membrane transport homeostasis thus seems to be 300–350, as found in bacteria, yeasts, and fungi. Many of the additional newly diverged genes of higher animals and plants are channel transporter genes and secondary active transporters that facilitate adaptation to fluctuating concentration gradients present in their environments. Moreover, many newly acquired transporters are highly specifically stage- and tissue-regulated and transport special substrates such as neurotransmitters (ACC) in neural cells or carbohydrates (POT) in leaf tissue. E. coli H. sapiens A. thaliana O. sativa 7 + + 7 Fig. 7 Summaries of comparison of membrane transport genes in bacteria, animals, and plants + + + + + + + + 2+ 2+ 2+  p + + 2+ + + + + + + + + + + + + 2+ 2+ 2+ + +  2+ 2+ 2+  + + + + + + + + + + + + + CPA2 DMT MFS MOP POT + 7 Conclusions Comparative analysis of membrane transporters among these eight diverse organisms indicates the type of cell homeostasis, as evidenced by the pattern of gene conservation and diversification. Evolutionary changes in gene families, in general, indicate the dynamics of alterations in biological systems and gene networks. Therefore, analysis of large categories of gene families may reveal many basic concepts of biological systems. In practice, analyses of the membrane transporter mechanism are useful in revealing changes in the absorption of molecules by, or their efflux from, cells and tissues. This information also is useful for examining changes in soil adaptability, nutritional demand, and stress tolerance in plants. It may also help to improve the harvest of crop cultivars or extend areas habitable by plant species. Gene networks are intricately related, and analysis of the whole genetic structure is needed to gain a full understanding of biological phenomena and systems of gene regulation. We are continuing to analyze whole categories of genes in an effort to develop an overview of total gene networks. Electronic supplementary material (DOC 21 kb) (XLS 189 kb) (PDF 151 kb) (PDF 192 kb) (PDF 165 kb)