Introduction 1990 1957 1990 1997 1997 2004 exportin 5/MSN5 HASTY HST 1998 2003 SERRATE SE 1999 ZIPPY ZIP 2003 zip SUPRESSOR OF GENE SILENCING3 SGS3 RNA-DEPENDENT POLYMERASE6 RDR6 ZIP HST 2004 dicer-like 4 dcl4 2005 2005 2005 One explanation for the observed effects could be that target genes of this silencing pathway play a positive role on the vegetative phase change and their down-regulation consequently promotes juvenility. Hence, mutations in genes involved in this silencing pathway, as the ones described above, cause an accelerated vegetative development. SPL3 1997 2006 SPL3 2002 2005 2006 2007 SPL3 SPL 2005 2006 SPL SPL SPL 2005 SPL9 SPL15 SPL9 SPL15 SQUAMOSA PROMOTER BINDING PROTEIN-LIKE SPL 1999 Materials and methods Plant material and plant growth conditions spl9 spl15 spl15 spl9 spl15 Arabidopsis http://signal.salk.edu En spl9 2001 SPL9 En 2 2 2 Phenotypic analysis −1 Histological analysis 4 A P −2 A P 3 spl9 spl15 35S::MIR156b 3 Phylogenetic comparison Multiple alignments of amino acid sequences were generated by the program ClustalW of the MacVector 7.2.2 software package (Accelrys Ltd., Cambridge, UK) using the BLOSUM 30 matrix with an open gap penalty of 10 and an extend gap penalty of 0.05. Only the SBP-domain was used for the phylogenetic reconstruction. The tree was constructed using the neighbour-joining algorithm of the MacVector 7.2.2 software package. Quantitative real-time PCR analysis SPL9 SPL15 2005 PP2A SPL9 SPL15 PP2A Semi-quantitative RT-PCR analysis SPL9 SPL9 SPL9 SPL15 SPL15 SPL15 RAN3 RAN3 RAN3 Statistics t P Remaining techniques and methods 1989 Results SPL9 SPL15 SPL9 SPL15 SPL SPL9 spl9 1 pl9 1998 2001 En spl9 spl9 2003 2007 Fig. 1 SPL9 SPL15 a SPL9 SPL15 b SPL9 SPL15 PP2A SPL9 c SPL9 SPL15 RAN3  SPL15 1 spl15 spl15 spl15 2005 SPL9 SPL15 1 SPL9 SPL15 SPL9 SPL15 SPL9 SPL15 SPL15 SPL15 SPL9 SPL15 1 spl9 spl15 SPL9 SPL15 SPL9 SPL15 SPL SPL9 SPL15 2 SPL9 SPL15 spl9 spl15 spl9 spl15 spl9 spl15 spl9 spl15 Fig. 2 Chlamydomonas SPL9 SPL15 SPL  spl9 spl15 spl9 spl15 spl9 spl15 35S::MIR156b MIR156b 2005 3 35S::MIR156b 3 spl9 spl15 3 SPL9 SPL15 MIR156b 1 35S::MIR156b spl9 spl15 MIR156b spl9 Fig. 3 spl9 spl15 a spl9 spl15 spl9 spl15 MIR156b b c spl9 spl15 b MIR156b c a  Table 1 spl9 spl15 35S::MIR156b  Rosette leaves Cauline leaves Bolting (DAS) Anthesis (DAS) a b Mean SD Mean SD Mean SD Mean SD Mean SD Mean SD Col-0 wt 13.1 1.1 3.9 0.5 16.3 1.2 20.9 1.5 5.5 1.2 12.1 1.3 spl9 14.3 1.1 c 0.7 15.9 1.4 c 1.7 8.3 0.8 8.0 1.0 spl9 15.6 1.2 c 0.5 16.9 1.2 20.8 1.4 9.2 0.9 8.2 0.8 spl9 15.7 1.3 c 0.6 c 1.5 21.3 1.5 9.6 0.7 8.6 0.8 spl15 15.6 1.1 c 0.4 16.6 0.8 20.9 1.0 7.1 0.7 10.3 1.2 spl15 14.9 1.0 3.5 0.5 17.1 1.9 20.9 1.9 7.3 0.8 c 1.1 spl15 16.1 1.0 3.7 0.7 c 0.8 21.8 1.1 7.6 0.7 c 1.3 spl9 spl15 19.5 d 1.4 3.4 0.9 18.5 d 1.4 c 1.8 10.9 d 0.8 6.9 d 1.4 spl9 spl15 18.9 d 1.3 c 0.6 19.0 d 1.5 c 1.8 10.8 d 0.4 6.8 d 0.8 35S::MIR156b 24.4 e 2.4 c 0.8 19.3 1.8 c 2.1 14.8 e 1.1 2.3 e 0.7 16 plants per genotype were used for determination DAS, days after sowing; SD, standard deviation Values significantly different from Col-0 wt at 0.001 confidence level are shown in italics a b c d e spl9 spl15 spl9 spl15 spl9 spl15 35S::MIR156b spl9 spl15 SPL9 SPL15 SPL9 SPL15 SPL 2002 MIR156b 2005 spl9 spl15 MIR156b SPL9 SPL15 SPL 1 spl9 spl15 2005 35S::MIR156b spl9 spl15 spl9 spl15 2005 MIR156b spl9 spl5 MIR156b MIR156b 4 35S::MIR156b 2005 Fig. 4 spl9 spl15 MIR156b a b pl9 spl15 MIR156b c  d c d e g d e g e pl9 spl15 f MIR156b g a d n e g e g e g  spl9 spl15 4 MIR156b P 4 spl9 spl15 MIR156b 4 spl9 spl15 MIR156b 4 MIR156b MIR156b spl9 spl15 4 4 MIR156b MIR156b 3 2 3 2 MIR156b 1997 SPL9 SPL15 1997 1 spl9 spl15 35S::MIR156b spl9 spl15 1 1990 spl9 spl15 MIR156b 2 MIR156b MIR156b SPL9 SPL15 SPL MIR156b Table 2 spl  a 1 D 3 D 5 D Col-0 wt 60 100 100 spl9 59 100 100 spl15 50 95 100 spl9 spl15 9 86 100 35S::MIR156b 0 27 100 D, days a SPL9 SPL15 1992 1997 spl9 spl15 MIR156b 3 5 3 spl9 spl15 MIR156b 3 spl9 spl15 MIR156b 3 3 Fig. 5 spl9 spl15 MIR156b 3 3 n  Discussion 2005 2006 2006 Corngrass1 2007 2005 2005 SPL SPL9 SPL15 SPL9 SPL15 SPL spl9 spl15 SPL2 MIR156b SPL2 spl2 n spl9 spl15 MIR156b SPL9 SPL15 MIR156b 2006 Corngrass1 2007 2006 SPL3 spl9 spl15 spl9 spl15 spl9 spl15 SPL9 SPL15 1 SPL9 SPL15 SPL9 SPL15 2003 SPL9 SPL15 SPL9 SPL15 SPL MIR156b SPL plastochron1 2 pla1, -2 1998 2004 2006 PLA1 PLA2 pla2 pla1 2000 2006 spl9 spl15 MIR156b SPL9 SPL15 SPL 2001 1967 2000 spl9 spl15 MIR156b 2004 2004 SPL9 SPL15 pla 2006 spl9 spl15 MIR156b MIR156b MIR156b MIR156b SPL9 SPL15 3 1997 spindly spy 1993 1997 1997 SPL9 SPL15 spl9 spl15 35S::MIR156b 3 SPL9 SPL15 SPL Outlook 2006 2005 2007 Electronic supplementary material Below is the link to the electronic supplementary material.
 Supplementary Fig. 1 SPL15 pSPL15::GUS:SPL15 SPL15 SPL15 SPL15 SPL15 A B A B A B Supplementary Fig. 2 spl9 spl15 A spl9 B spl15 C spl9 spl15 spl9 spl15 spl2 spl9 spl15