title: The expression of genes coding for auxin carriers in different tissues and along the organ can explain variations in auxin transport and the growth pattern in etiolated lupin hypocotyls.
abstract: Novel cDNA clones encoding putative auxin influx and efflux carriers have been isolated and characterized from etiolated lupin (Lupinus albus L) hypocotyls. The full length of LaAUX1 and LaPIN1 and the partial length of LaPIN3 were obtained and the deduced amino acid sequence revealed a high degree of identity with the corresponding auxin carrier proteins from several species. The expression of these genes depended on the tissue, the hypocotyl zone and seedling age. LaAUX1 and LaPIN3 were expressed in stele and outer tissues, while LaPIN1 was restricted to the stele. From the above-mentioned results and taking into account the role proposed for the efflux carrier PIN1, it is suggested that LaPIN1 could mediate the basipetal auxin transport already described in this organ. LaAUX1 might facilitate auxin influx in the transport cells. The expression of the three genes decreased down the hypocotyl. The basipetally decreasing gradient in the expression of LaPIN1 coincides with previous results showing a similar gradient in the intensity and polarity of auxin transport. The decisive role ascribed to PIN1 in polar auxin transport due to its localization in the basal end of transporting cells and the existence of such a gradient in the expression of LaPIN1 support the hypothesis of a barrier effect (generated by decreasing auxin transport) previously proposed by our research group as being responsible for the auxin gradient, which controls the growth pattern in etiolated lupin hypocotyls.
authors: Departamento de Biología Vegetal (Fisiología Vegetal), Facultad de Biología, Universidad de Murcia, Campus de Espinardo, 30100, Murcia, Spain.
authors: M Rocío
authors: MR
authors: Oliveros-Valenzuela
authors: David
authors: D
authors: Reyes
authors: José
authors: J
authors: Sánchez-Bravo
authors: Manuel
authors: M
authors: Acosta
authors: Carlos
authors: C
authors: Nicolás
mesh_terms: D000595:Amino Acid Sequence; D001692:Biological Transport / Q000235:genetics / Q000502:physiology; D015152:Blotting, Northern; D015139:Blotting, Southern; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D018546:Hypocotyl / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D007210:Indoleacetic Acids / Q000378:metabolism*; D031297:Lupinus / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D008954:Models, Biological; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D036226:Seedlings / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid
chemical_list: D018076:DNA, Complementary; D007210:Indoleacetic Acids; D010940:Plant Proteins
references: Nature. 2005 Jun 30;435(7046):1251-6
references: 15988527
references: Plant Physiol. 1998 Aug;117(4):1473-86
references: 9701602
references: Proc Natl Acad Sci U S A. 1988 Apr;85(8):2444-8
references: 3162770
references: Plant Physiol. 2001 Jun;126(2):524-35
references: 11402184
references: Nature. 2001 Sep 27;413(6854):425-8
references: 11574889
references: Plant J. 2002 Nov;32(4):509-17
references: 12445122
references: Plant Physiol. 2004 Jan;134(1):28-31
references: 14730061
references: Plant Physiol. 1992 Sep;100(1):108-14
references: 16652931
references: Planta. 2003 Nov;218(1):15-26
references: 12905024
references: Nature. 2002 Feb 14;415(6873):806-9
references: 11845211
references: EMBO J. 1996 May 1;15(9):2115-24
references: 8641277
references: Cell. 2003 Nov 26;115(5):591-602
references: 14651850
references: J Plant Physiol. 2007 Jul;164(7):851-60
references: 16904231
references: Plant Cell. 2004 Jul;16(7):1898-911
references: 15208397
references: Plant Cell. 2002 Mar;14(3):589-97
references: 11910006
references: Physiol Plant. 2004 Jun;121(2):294-304
references: 15153197
references: Planta. 1987 Feb;170(2):168-80
references: 24232875
references: Planta. 1991 Oct;185(3):391-6
references: 24186424
references: Plant Physiol. 1997 May;114(1):295-305
references: 9159952
references: Cell. 1996 Apr 19;85(2):183-94
references: 8612271
references: Plant Physiol. 1998 Feb;116(2):455-62
references: 9489005
references: Plant Physiol. 2001 Jun;126(2):536-48
references: 11402185
references: Science. 1998 Dec 18;282(5397):2226-30
references: 9856939
references: Genes Dev. 2001 Oct 15;15(20):2648-53
references: 11641271
references: Plant Cell. 2007 Jan;19(1):131-47
references: 17237354
references: Plant Physiol. 1992 Jul;99(3):808-11
references: 16669004
references: Nature. 2003 Jun 26;423(6943):999-1002
references: 12827205
references: Planta. 2003 Jan;216(3):366-76
references: 12520327
references: J Theor Biol. 1988 Oct 21;134(4):547-59
references: 3255010