Highly pleiotropic functions of CYP78As and AMP1 are regulated in non-cell-autonomous/organ-specific manners

Abstract The cytochrome P450 CYP78A5/KLUH in Arabidopsis thaliana is predicted to be involved in the synthesis of a mobile signal molecule that has a pleiotropic function that is distinct from classical phytohormones. CYP78A5 has five close relatives in Arabidopsis. We first investigated their functions, focusing on the plastochron, leaf size, and leaf senescence. Our analyses revealed that CYP78A5 and CYP78A7 are involved in the plastochron and leaf size, and CYP78A6 and CYP78A9 are involved in leaf senescence. Complementation analyses using heterologous promoters and expression analyses suggested that CYP78A isoforms have a common biochemical function and are functionally differentiated via organ-specific expression. The altered meristem program1 (amp1) carboxypeptidase mutant shows a phenotype very similar to that of the cyp78a5 mutant. Complementation analyses using boundary- and organizing center-specific promoters suggested that both CYP78A5 and AMP1 act in a non-cell-autonomous manner. Analyses of multiple cyp78a mutants and crosses between cyp78a and amp1 mutants revealed that AMP1/LIKE AMP1 (LAMP1) and CYP78A isoforms regulate plastochron length and leaf senescence in the same genetic pathway, whereas leaf size is independently regulated. Furthermore, we detected feedback regulation between CYP78A6/CYP78A9 and AMP1 at the gene expression level. These observations raise the possibility that AMP1 and CYP78A isoforms are involved in the synthesis of the same mobile signal molecule, and suggest that AMP1 and CYP78A signaling pathways have a very close, albeit complex, functional relationship.s

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Investigating Tissue- and Organ-specific Phytochrome Responses using FACS-assisted Cell-type Specific Expression Profiling in Arabidopsis thaliana

Journal of Visualized Experiments ◽

10.3791/1925 ◽

2010 ◽

Author(s):

Sankalpi N. Warnasooriya ◽

Beronda L. Montgomery

Keyword(s):

Arabidopsis Thaliana ◽

Expression Profiling ◽

Cell Type ◽

Specific Expression ◽

Organ Specific ◽

Cell Type Specific Expression ◽

Cell Type Specific

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Drosophila PDGF/VEGF signaling from muscles to hepatocyte-like cells protects against obesity

eLife ◽

10.7554/elife.56969 ◽

2020 ◽

Vol 9 ◽

Cited By ~ 1

Author(s):

Arpan C Ghosh ◽

Sudhir Gopal Tattikota ◽

Yifang Liu ◽

Aram Comjean ◽

Yanhui Hu ◽

...

Keyword(s):

Adipose Tissue ◽

Lipid Level ◽

Lipid Synthesis ◽

Tissue Lipid ◽

Tor Signaling ◽

Specific Expression ◽

Signaling Axis ◽

Organ Specific ◽

Lipid Stores ◽

Multicellular Organisms

PDGF/VEGF ligands regulate a plethora of biological processes in multicellular organisms via autocrine, paracrine, and endocrine mechanisms. We investigated organ-specific metabolic roles of Drosophila PDGF/VEGF-like factors (Pvfs). We combine genetic approaches and single-nuclei sequencing to demonstrate that muscle-derived Pvf1 signals to the Drosophila hepatocyte-like cells/oenocytes to suppress lipid synthesis by activating the Pi3K/Akt1/TOR signaling cascade in the oenocytes. Functionally, this signaling axis regulates expansion of adipose tissue lipid stores in newly eclosed flies. Flies emerge after pupation with limited adipose tissue lipid stores and lipid level is progressively accumulated via lipid synthesis. We find that adult muscle-specific expression of pvf1 increases rapidly during this stage and that muscle-to-oenocyte Pvf1 signaling inhibits expansion of adipose tissue lipid stores as the process reaches completion. Our findings provide the first evidence in a metazoan of a PDGF/VEGF ligand acting as a myokine that regulates systemic lipid homeostasis by activating TOR in hepatocyte-like cells.

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Neuropeptides in modulation of Drosophila behavior: how to get a grip on their pleiotropic actions

10.7287/peerj.preprints.27531 ◽

2019 ◽

Author(s):

Dick R Nässel ◽

Dennis Pauls ◽

Wolf Huetteroth

Keyword(s):

Expression Pattern ◽

Internal State ◽

Neurosecretory Cells ◽

Higher Order ◽

Specific Expression ◽

Specific Expression Pattern ◽

Pleiotropic Functions ◽

Pleiotropic Actions ◽

The Brain ◽

Different Levels

Neuropeptides constitute a large and diverse class of signaling molecules that are produced by many types of neurons, neurosecretory cells, endocrines and other cells. Many neuropeptides display pleiotropic actions either as neuromodulators, co-transmitters or circulating hormones, while some play these roles concurrently. Here, we highlight pleiotropic functions of neuropeptides and different levels of neuropeptide signaling in the brain, from context-dependent orchestrating signaling by higher order neurons, to local executive modulation in specific circuits. Additionally, orchestrating neurons receive peptidergic signals from neurons conveying organismal internal state cues and relay these to executive circuits. We exemplify these levels of signaling with four neuropeptides, SIFamide, short neuropeptide F, allatostatin-A and leucokinin, each with a specific expression pattern and level of complexity in signaling.

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Temperature and leaf area expansion of sugarcane: integration of controlled-environment, field and model studies

Functional Plant Biology ◽

10.1071/pp98042 ◽

1998 ◽

Vol 25 (7) ◽

pp. 819 ◽

Cited By ~ 24

Author(s):

Michael J. Robertson ◽

Graham D. Bonnett ◽

R. Michael Hughes ◽

Russell C. Muchow ◽

James A. Campbell

Keyword(s):

Leaf Area ◽

Leaf Senescence ◽

Leaf Size ◽

Field Studies ◽

Growth Conditions ◽

Thermal Time ◽

Leaf Position ◽

Potential Growth ◽

Leaf Stage ◽

Leaf Appearance

Canopy development is an important determinant of crop radiation interception, and in the absence of stress is mainly driven by temperature. The responses to temperature of the component processes of canopy dynamics in sugarcane: leaf appearance, leaf size, tillering, and leaf senescence, were analysed for the commercial Australian cultivar, Q117. Data were derived under optimal growth conditions from controlled environments, and from irrigated field studies in subtropical and tropical locations. Regression of number of fully-expanded leaves in field-grown plants against cumulative thermal time revealed that the thermal time between the appearance of successive leaves increased as a function of leaf number, such that leaf 1 required 86˚Cd and leaf 40 required 160˚Cd. At any moment, on average there were 3.7 leaves still expanding on the stalks. Functions describing leaf appearance gave acceptable prediction of the time course of leaf appearance taken from independent datasets of field-grown plant and ratoon crops. Leaf size increased with leaf position, with the largest leaves observed at approximately leaf 17 and above. Combining functions describing leaf appearance and leaf size as a function of leaf position allowed estimation of leaf area index (LAI) of main stems in plant and ratoon crops in subtropical and tropical environments. Tiller LAI, derived by difference, accounted for 60–90% of total LAI at the 5- leaf stage, declining to 20–50% at the 15-leaf stage. Plant and ratoon crops were similar in terms of the amount and proportion of tiller LAI. Combining data from all field studies indicated under potential growth conditions, leaf senescence was closely related to leaf production. The functions derived in this study give a basis for simulating canopy dynamics under potential growth conditions in sugarcane, though the extent of genotypic variation for the key parameters and their modification by stress remains to be assessed.

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