In plants, flowering is triggered by endogenous and environmental signals. CONSTANS (CO) promotes of Arabidopsis in response to day length. Four early target genes CO were identified using a steroid-inducible version the protein. Two these genes, SUPPRESSOR OF OVEREXPRESSION 1 ( SOC1 ) FLOWERING LOCUS T FT ), are required for promote flowering; others involved proline or ethylene biosynthesis. The also regulated second flowering-time pathway that acts independently CO. Thus, define common...

Many plants flower in response to seasonal fluctuations day length. The CONSTANS (CO) gene of Arabidopsis promotes flowering long days. Flowering is induced when CO messenger RNA expression coincides with the exposure light. However, how this activity unknown. We show that light stabilizes nuclear protein evening, whereas morning or darkness degraded by proteasome. Photoreceptors regulate stability and act antagonistically generate daily rhythms abundance. This layer regulation refines...

Abstract The CCT (for CONSTANS, CONSTANS-LIKE, TOC1) domain is found in 45 Arabidopsis thaliana proteins involved processes such as photoperiodic flowering, light signaling, and regulation of circadian rhythms. We show that this exhibits similarities to yeast HEME ACTIVATOR PROTEIN2 (HAP2), which a subunit the HAP2/HAP3/HAP5 trimeric complex binds CCAAT boxes eukaryotic promoters. Moreover, we demonstrate CONSTANS (CO), promotes interacts with At HAP3 HAP5 yeast, vitro, planta. Mutations CO...

Leaves are formed at the flanks of shoot apical meristem (SAM) and develop into a variety forms. In tomato, prolonged leaf patterning enables elaboration compound leaves by reiterative initiation leaflets with lobed margins. goblet (gob) loss-of-function mutants,primary often fused, secondary marginal serrations absent, SAMs terminate precociously. We show that GOBencodes NAC-domain transcription factor expressed in narrow stripes margins, flanking distal side future leaflet primordia,...

Summary CONSTANS‐Like (COL) proteins are plant‐specific nuclear regulators of gene expression but do not contain a known DNA‐binding motif. We tested whether common protein can deliver these to specific cis‐acting elements. screened for that interact with two members subgroup COL proteins. These were Tomato COL1 (TCOL1), which does seem be involved in the control flowering time, and Arabidopsis thaliana CONSTANS (AtCO) mediates photoperiodic induction flowering. show C‐terminal CCT (CO,...

Summary Genetic and molecular studies have suggested that the UNUSUAL FLORAL ORGANS ( UFO ) gene, from Arabidopsis thaliana, is expressed in all shoot apical meristems, involved regulation of a complex set developmental events during floral development, including meristem organ identity. Results situ hybridization using genes early development as probes indicate controls growth young primordia. Transgenic constructs were used to provide evidence regulates identity by activating or...

Interactions between TALE (three–amino acid loop extension) homeodomain proteins play important roles in the development of both fungi and animals. Although plants, two different subclasses include developmental regulators, existence interactions plant has remained unexplored. We have used yeast two-hybrid system to demonstrate that Arabidopsis BELL1 (BEL1) protein can selectively heterodimerize with specific KNAT proteins. Interaction is mediated by BEL1 sequences N terminal including...

Abstract The transition to flowering involves major changes in the shoot apical meristem and fate of existing leaf primordia. Transcripts Arabidopsis thaliana flowering-promoting gene FLOWERING LOCUS T (FT) are present tissue but can also promote when artificially introduced into meristem. FT may normally act and/or meristem, initiating or constituting a mobile flower-promoting signal. We studied FT-dependent events rosette leaf, some which might precede mimic its show transcript...

Leaf senescence is a programmed developmental process governed by various endogenous and exogenous factors, such as the plant stage, leaf age, phytohormone levels, darkness, exposure to stresses. It was found that, in addition its well-documented role enhancement of frost tolerance, overexpression C-repeat/dehydration responsive element binding factor 2 (CBF2) gene Arabidopsis delayed onset extended life span plants approximately weeks. This phenomenon exhibited both during detached leaves...

Olive (Olea europaea L.) inflorescences, formed in lateral buds, flower spring. However, there is some debate regarding time of induction and inflorescence initiation. juvenility seasonality flowering were altered by overexpressing genes encoding locus T (FT). OeFT1 OeFT2 caused early under short days when expressed Arabidopsis. Expression OeFT1/2 olive leaves buds increased winter, while initiation inflorescences occurred i n late winter. Trees exposed to an artificial warm winter low...

In many perennials, heavy fruit load on a shoot decreases the ability of plant to undergo floral induction in following spring, resulting pattern crop production known as alternate bearing. Here, we studied effects determination 'Hass' avocado (Persea americana). De-fruiting experiments initially confirmed negative return flowering. Next, isolated FLOWERING LOCUS T-like gene, PaFT, hypothesized act phloem-mobile florigen signal and examined its expression profile tissues (fully loaded) off...

In many perennial fruit trees, flowering in the year following a with heavy load can be quite limited. This biennial cycle of fruiting, termed alternate bearing, was described 170 years ago apple (Malus domestica). Apple inflorescences are mainly found on short branches (spurs). Bourse shoots (BS) develop from leaf axils spur. BS apices may terminate ~100 days after flowering, formation next year's inflorescences. We sought to determine how developing spur prevents adjacent apex forming an...

Carbon reserve use is a major drought response in trees, enabling tree survival conditions prohibiting photosynthesis. However, regulation of starch metabolism under at the whole-tree scale still poorly understood. To this end, we combined measurements nonstructural carbohydrates (NSCs), physiology and gene expression. The experiment was conducted outside on olive trees pots 90 d seasonal spring to summer warming. Half were also subjected limited water for 28 d. Photosynthesis decreased...

The gene encoding the plant biosynthetic threonine deaminase (Td; EC 4.2.1.16) has been cloned as a result of its unusual upregulation in tomato flowers. Td encodes polypeptide 595 residues, first 80 which comprise putative two-domain transit peptide cleaved at position 51. Comparison amino acid sequence with corresponding enzymes from yeast and bacteria reveals near identity important catalytic regions greater than 40% overall similarity. is unique genome coding region interrupted by eight...

Climate change, with elevated temperatures throughout the year, affects many stages of reproductive growth and development olives as well oil quality at harvest. Although olive (Olea europaea L.) is adapted to environmental conditions Mediterranean Basin, agricultural techniques breeding through selection programs will have adapt these climate threatening worsen in near future. Defining pathways controlling high fruit productivity quantity quality, despite sub-optimal growing conditions,...

Regulatory mechanisms controlling basic aspects of floral morphogenesis seem to be highly conserved among plant species. The class B organ identity genes, which are required establish the organs in second (petals) and third (stamens) whorls, a good example such conservation. This work compares function two similar genes same genetic background. DEFICIENS (DEF) gene from Antirrhinum, including its promoter, was transformed into Arabidopsis compared expression with APETALA3 (AP3) PISTILLATA...