Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0282612 (PIN)
 2,291 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Perception of elicitors triggers plant defense responses via various early signal transduction pathways. Methyl jasmonate (MeJA) stimulates defense responses in grapevine (Vitis vinifera). We investigated the involvement of various partners (calcium, ROS, reversible phosphorylation) in MeJA-induced responses by using a pharmacological approach. We used specific calcium channel effectors and inhibitors of serine/threonine phosphatases, superoxide dismutase and NAD(P)H oxidase and investigated production of stilbenes (resveratrol and its glucoside, piceid, the major form), which are the grapevine phytoalexins. RNA accumulation of two genes encoding enzymes involved in stilbene synthesis (PAL and STS), three genes encoding pathogenesis-related proteins (CHIT4C, PIN and GLU) and one gene encoding an enzyme producing jasmonates (LOX) were also assessed. Calcium and its origin seemed to play a major role in MeJA-induced grapevine defense responses. Phytoalexin production was strongly affected if calcium from the influx plasma membrane was inhibited, whereas calcium from the intracellular compartments did not seem to be involved. ROS production seemed to interfere with MeJA-stimulated defense responses, and protein phosphorylation/dephosphorylation events also played a direct role.
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PMID:Implication of signaling pathways involving calcium, phosphorylation and active oxygen species in methyl jasmonate-induced defense responses in grapevine cell cultures. 1963 5

Within a multicellular tissue cells may coordinately form a singular or multiple polar axes, but it is unclear whether a common mechanism governs different types of polar axis formation. The phosphorylation status of PIN proteins, which is directly affected by the PINOID (PID) protein kinase and the PP2A protein phosphatase, is known to regulate the apical-basal polarity of PIN localization in bipolar cells of roots and shoot apices. Here, we provide evidence that the phosphorylation status-mediated PIN polarity switch is widely used to modulate cellular processes in Arabidopsis including multipolar pavement cells (PC) with interdigitated lobes and indentations. The degree of PC interdigitation was greatly reduced either when the FYPP1 gene, which encodes a PP2A called phytochrome-associated serine/threonine protein phosphatase, was knocked out or when the PID gene was overexpressed (35S::PID). These genetic modifications caused PIN1 localization to switch from lobe to indentation regions. The PP2A and PID mediated switching of PIN1 localization is strikingly similar to their regulation of the apical-basal polarity switch of PIN proteins in other cells. Our findings suggest a common mechanism for the regulation of PIN1 polarity formation, a fundamental cellular process that is crucial for pattern formation both at the tissue/organ and cellular levels.
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PMID:Phosphorylation switch modulates the interdigitated pattern of PIN1 localization and cell expansion in Arabidopsis leaf epidermis. 2142 79

The PIN and ACO gene families present interesting questions about the evolution of plant physiology, including testing hypotheses about the ecological drivers of their diversification and whether unrelated genes have been recruited for similar functions. The PIN-formed proteins contribute to the polar transport of auxin, a hormone which regulates plant growth and development. PIN loci are categorized into groups according to their protein length and structure, as well as subcellular localization. An interesting question with PIN genes is the nature of the ancestral form and location. ACOs are members of a superfamily of oxygenases and oxidases that catalyze the last step of ethylene synthesis, which regulates many aspects of the plant life cycle. We used publicly available PIN and ACO sequences to conduct phylogenetic analyses. Third codon positions of these genes in monocots have a high GC content, which could be historical but is more likely due to a mutational bias. Thus, we developed methods to extract phylogenetic information from nucleotide sequences while avoiding this convergent feature. One method consisted in using only A-T transformations, and another used only the first and second codon positions for serine, which can only take A or T and G or C, respectively. We also conducted tree-searches for both gene families using unaligned amino acid sequences and dynamic homology. PIN genes appear to have diversified earlier than ACOs, with monocot and dicot copies more mixed in the phylogeny. However, gymnosperm PINs appear to be derived and not closely related to those from primitive plants. We find strong support for a long PIN gene ancestor with short forms subsequently evolving one or more times. ACO genes appear to have diversified mostly since the dicot-monocot split, as most genes cluster into a small number of monocot and dicot clades when the tree is rooted by genes from mosses. Gymnosperm ACOs were recovered as closely related and derived.
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PMID:A novel phylogeny and morphological reconstruction of the PIN genes and first phylogeny of the ACC-oxidases (ACOs). 2501 60

Regulation of protein function by phosphorylation and dephosphorylation is an important mechanism in many cellular events. The phototropin blue-light photoreceptors, plant-specific AGCVIII kinases, are essential for phototropic responses. Members of the D6 PROTEIN KINASE (D6PK) family, representing a subfamily of the AGCVIII kinases, also contribute to phototropic responses, suggesting that possibly further AGCVIII kinases may potentially control phototropism. The present study investigates the functional roles of Arabidopsis (Arabidopsis thaliana) AGCVIII kinases in hypocotyl phototropism. We demonstrate that D6PK family kinases are not only required for the second but also for the first positive phototropism. In addition, we find that a previously uncharacterized AGCVIII protein, AGC1-12, is involved in the first positive phototropism and gravitropism. AGC1-12 phosphorylates serine residues in the cytoplasmic loop of PIN-FORMED 1 (PIN1) and shares phosphosite preferences with D6PK. Our work strongly suggests that the D6PK family and AGC1-12 are critical components for both hypocotyl phototropism and gravitropism, and that these kinases control tropic responses mainly through regulation of PIN-mediated auxin transport by protein phosphorylation.
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PMID:Roles of AGCVIII Kinases in the Hypocotyl Phototropism of Arabidopsis Seedlings. 2949 64