Table 1.
Auxin transport genes in maize.
Fig 1.
Chromosomal distribution and expansion patterns of maize auxin transporter encoding genes.
(A) The genome visualization tool SyMAP Synteny Browser was employed (http://www.symapdb.org/) to analyze the maize genome. Maize chromosomes were arranged in blocks. Fifteen ZmPIN genes, nine ZmPILS genes, five ZmLAX genes and thirty-five ZmABCB genes were among ten chromosomes. ZmPIN, ZmPILS, ZmLAX and ZmABCB family genes are mapped by locus and the gene clusters were indicated by red boxes. (B) Gene segmental duplications were showed with dotted arrows.
Fig 2.
Phylogenetic relationship analysis of auxin transporter family between maize, Arabidopsis and rice.
Bootstrap values are presented for all branches. (A) LAX protein family: inventory of AtLAX and OsLAX families is based on TAIR and TIGR rice databases. (B) PIN protein family: sequence data on AtPIN and OsPIN families is based on TAIR annotation and Shen’s publish. (C) PILS protein families: inventory of AtPILS and OsPILS families is listed at S1 Table. (D) ABCB protein family: inventory of AtABCB and OsABCB families is based on the ABC superfamily review by Verrier et al. Different colors indicated different subfamilies. The ortholog genes between maize and Arabidopsis or rice were indicated by green dotted boxes. The paralog genes within maize were indicated by red dotted boxes.
Fig 3.
Tissues-specific expressions and exon-intron structures of ZmLAX, ZmPIN, ZmPILS and ZmABCB genes.
(A) Tissues-specific expression patterns of ZmLAX, ZmPIN, ZmPILS and ZmABCB genes. L: leaf; R: root; S: shoot; F: flower. Levels of different colors were shown on a log scale from the high to the low expression of each ZmPIN, ZmPILS, ZmLAX and ZmABCB gene. The expression level of ZmACTIN or 18S RNA gene were defined as log (10000) = 4. (B) Exon-intron structure analysis of ZmLAX, ZmPIN, ZmPILS and ZmABCB genes. The exons were indicated by blue boxes; the introns were indicated by gray lines.
Fig 4.
Real-time quantitative RT-PCR (qRT-PCR) analysis of ZmLAX, ZmPIN, ZmPILS and ZmABCB genes in plants under IAA treatment in both shoots (A) and roots (B).
Total RNA was extracted from the seedlings shoots and roots of maize for expression analysis. The histogram shows the relative expression levels of ZmLAX, ZmPIN, ZmPILS and ZmABCB genes under IAA treatment (10 μM, 48 hours) compared to the mock expression level. Untreated seedlings were used as mock seedlings. The relative mRNA level of individual genes was normalized with respect to the ZmACTIN gene (defines as 1). The data were analyzed by five independent repeats, and standard deviations were shown with error bars.
Fig 5.
Expression levels of ZmPIN, ZmPILS, ZmLAX and ZmABCB gene families in response to salt.
Expression levels of ZmPIN, ZmPILS, ZmLAX and ZmABCB genes were analyzed by qRT-PCR in both shoot (A) and roots (B) of 14-day-old seedlings, which were treated with 150 mM NaCl (salt) for 48 hours. The relative expression levels were normalized to a value of 1 in mock seedlings. Error bars represent SD from five biological replicates.
Fig 6.
Expression levels of ZmPIN, ZmPILS, ZmLAX and ZmABCB gene families in response to drought.
Expression levels of ZmPIN, ZmPILS, ZmLAX and ZmABCB genes were analyzed by qRT-PCR in both shoot (A) and roots (B) of 14-day-old seedlings, which were treated with dry sand treatment (drought) for 3 days. The relative expression levels were normalized to a value of 1 in mock seedlings. Error bars represent SD from five biological replicates.
Fig 7.
Expression levels of ZmPIN, ZmPILS, ZmLAX and ZmABCB gene families in response to cold.
Expression levels of ZmPIN, ZmPILS, ZmLAX and ZmABCB genes were analyzed by qRT-PCR in both shoot (A) and roots (B) of 14-day-old seedlings, which were treated with cold (4°C) for 48 hours. The relative expression levels were normalized to a value of 1 in mock seedlings. Error bars represent SD from five biological replicates.