Project description:CRABS CLAW (CRC) encodes a transcription factor of the plant-specific YABBY class in the model plant Arabidopsis thaliana. This gene is highly expressed in the abaxial (external) domain of the gynoecium wall and contributes to the establishment of abaxial-adaxial (external-internal) polarity in that tissue. Here we derive a list of putative target genes of CRC, which include AUXIN RESPONSE FACTOR4 (ARF4) and ASSYMETRIC LEAVES1 (AS1), both of which are known to be involved in the establishment of abaxial-adaxial polarity in lateral organs. ETTIN (ETT), which is partially redundant with ARF4, was not identified as a direct target of CRC, and this observation led us to predict that crc/ett double mutants might resemble ett/arf4 double mutants, which show a very strong breakdown of abaxial-adaxial polarity in the gynoecium wall. We have confirmed this prediction by constructing double mutants using several available mutant alleles of crc, ett and arf4. Interestingly, AS1 plays a role in the establishment of adaxial tissue identity in lateral organs, though its expression is not restricted to the adaxial domain. The observed positive regulation of AS1 by CRC may thus occur very early in gynoecium development, before CRC expression becomes polarised, or at later stages of development, specifically in the abaxial domain.
Project description:The WOX1 transcription factor is a multifunctional regulator of lateral-organ development that acts as a transcriptional repressor. WOX1 promotes lamina growth, controls marginal tissue differentiation and is involved in establishment and maintenance of the adaxial-abaxial pattern from the middle domain of leaf primordia. To identify the WOX1 downstream genes, we performed a microarray analysis of shoot apices of transgenic Arabidopsis thaliana lines harboring 35S::WOX1:glucocorticoid receptor (GR) in which the WOX1 function was temporarily enhanced by dexamethasone (DEX).
Project description:What methylation changes are occurring in different compartments of early maturation stage seed largely remains unknown. To uncover the possible role of DNA methylation in different compartments of early maturation stage seed, we characterized the methylome of two major compartments in embryonic cotyledon: cotyledon abaxial parenchyma (EM-COT-ABPY) and cotyledon adaxial parenchyma (EM-COT-ADPY) using Illumina sequencing. Illumina sequencing of bisulfite-converted genomic DNA from cotyledon abaxial parenchyma (EM-COT-ABPY) and cotyledon adaxial parenchyma (EM-COT-ADPY) compartments.
Project description:Leaves are asymmetric, with differential functionalization of abaxial and adaxial tissues. The bundle sheath (BS) surrounding the vasculature of the C3 crop barley is dorsoventrally differentiated into three domains: adaxial structural, lateral S-type, and abaxial L-type. S-type cells seem to transfer assimilates towards the phloem. Here we used single-cell RNA sequencing to investigate BS differentiation in C4 maize. Abaxial BS (abBS) cells of rank-2 intermediate veins specifically expressed three SWEET sucrose uniporters (SWEET13a, b, and c) and UmamiT amino acid efflux transporters. SWEET13a, b, c were also identified in the phloem parenchyma (PP). Thus maize acquired a unique mechanism for phloem loading in which abBS cells provide the main pathway for apoplasmic sucrose transfer towards the phloem. This pathway predominates in veins responsible for phloem loading (rank-2 intermediate), while rank-1 intermediate and major veins export sucrose from the phloem parenchyma (PP) adjacent to the sieve element companion cell (SE/CC) complex, as in Arabidopsis. We surmise that abBS identity is subject to dorsoventral patterning and has components of PP identity. The observations provide first insights into the unique properties of abBS cells, cells previously considered to fulfill the same functions as other bundle sheath cells (BSCs), and a basis for understanding the C4 syndrome.
Project description:Leaves are asymmetric, with differential functionalization of abaxial and adaxial tissues. The bundle sheath (BS) surrounding the vasculature of the C3 crop barley is dorsoventrally differentiated into three domains: adaxial structural, lateral S-type, and abaxial L-type. S-type cells seem to transfer assimilates towards the phloem. Here we used single-cell RNA sequencing to investigate BS differentiation in C4 maize. Abaxial BS (abBS) cells of rank-2 intermediate veins specifically expressed three SWEET sucrose uniporters (SWEET13a, b, and c) and UmamiT amino acid efflux transporters. SWEET13a, b, c were also identified in the phloem parenchyma (PP). Thus maize acquired a unique mechanism for phloem loading in which abBS cells provide the main pathway for apoplasmic sucrose transfer towards the phloem. This pathway predominates in veins responsible for phloem loading (rank-2 intermediate), while rank-1 intermediate and major veins export sucrose from the phloem parenchyma (PP) adjacent to the sieve element companion cell (SE/CC) complex, as in Arabidopsis. We surmise that abBS identity is subject to dorsoventral patterning and has components of PP identity. The observations provide first insights into the unique properties of abBS cells, cells previously considered to fulfill the same functions as other bundle sheath cells (BSCs), and a basis for understanding the C4 syndrome.
Project description:Analyis gene expression in crc-1 knu-1 compared with knu-1 Initiation of the carpel primordia is marked by the termination of floral stem cells. Although genetic evidences have suggested that the YABBY gene CRABS CLAW (CRC) regulates the development of carpel, as well as the floral meristem determinacy as a target of the homeotic protein AGAMOUS, the underlying mechanism remains unclear. Here we show that the tetraspanin-encoding gene TONADO2 (TRN2) and the auxin biosynthesis gene YUCCA4 (YUC4) act as downstream targets of CRC.
Project description:ENF1 gene (AT1G79440) encodes succinic semialdehyde dehydrogenase. Loss-of-function mutant of ENF1 shows pleiotropic phenotypes, including abnormal gene expression along the adaxial-abaxial axis in leaf development. enf1-1 allele has a point mutation in the splicing accepter site of 11th intron of ENF1. enf1-6 allele has T-DNA insertion in 5th exon of ENF1.
2013-10-21 | GSE24895 | GEO
Project description:Transcriptomic analysis of abaxial/adaxial light supplementation in tomato leaves
Project description:Fruit length is a key domestication trait that affects crop yield and appearance quality. Cucumber fruits vary from 5~60 cm in length. Despite multiple fruit length QTLs have been identified, the underlying genes and regulatory mechanisms are poorly understood. Map-based cloning identified a nonsynonymous SNP (G to A) in CRABS CLAW (CsCRC) confers the major effect fruit length QTL FS5.2. CsCRCA is a rare allele only exist in Xishuangbanna cucumber with round fruits. Construction of near-isogenic line (NIL) of CsCRCA led to 34~39% reduction in fruit length. Introduction of CsCRCG into the NIL rescued the short-fruit phenotype, and knockdown of CsCRCG resulted in reduced fruit length and decreased cell size. RNA-seq results showed that an auxin responsive protein CsARP1 expressed decreased in CsCRC-RNAi lines. Further, an auxin responsive protein Further, CsARP1 is the downstream target gene of CsCRCG, instead of CsCRCA. Knockout of CsARP1 produced decreased fruit length with smaller cells. Hence, our work suggested that CsCRCG positively regulates fruit elongation through transcriptional activation of CsARP1 and thus enhanced cell expansion. Utilization of CsCRC alleles provides a new strategy to manipulate fruit length in cucumber breeding.