Distinct domains within the NITROGEN LIMITATION ADAPTATION protein mediate its subcellular localization and function in the nitrate-dependent phosphate homeostasis pathway

The NITROGEN LIMITATION ADAPTATION (NLA) protein is a RING-type E3 ubiquitin ligase that plays an essential role in the regulation of nitrogen and phosphate homeostasis. NLA is localized to two different subcellular sites (the plasma membrane and the nucleus), and contains four distinct domains: (i) a RING domain that mediates degradation of phosphate transporters at the plasma membrane; (ii) an SPX domain that facilitates NLA’s interaction with the phosphate transporters, and also exists in other proteins that regulate the nuclear transcription factors that control the phosphate starvation response pathway; (iii) a linker domain that lies between the RING and SPX domains; and (iv) a C-terminal domain, which, like the linker region, is of unknown function. Here we carried out a mutational analysis of NLA, which indicated that all the domains are not only essential for proper functioning of the protein, but also mediate its localization to the plasma membrane and (or) nucleus, as well as to different subdomains within the nucleus. Overall, the results provide new insights to the distinct protein motifs within NLA and the role(s) that this protein serves at different subcellular sites with respect to the regulation of nitrogen-dependent phosphate homeostasis as well as other possible physiological functions.

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Faculty Opinions recommendation of Nitrogen limitation adaptation, a target of microRNA827, mediates degradation of plasma membrane-localized phosphate transporters to maintain phosphate homeostasis in Arabidopsis.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.718140806.793487448 ◽

2013 ◽

Author(s):

Jian Feng Ma

Keyword(s):

Plasma Membrane ◽

Nitrogen Limitation ◽

Phosphate Homeostasis ◽

Phosphate Transporters

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NITROGEN LIMITATION ADAPTATION, a Target of MicroRNA827, Mediates Degradation of Plasma Membrane–Localized Phosphate Transporters to Maintain Phosphate Homeostasis in Arabidopsis

The Plant Cell ◽

10.1105/tpc.113.116012 ◽

2013 ◽

Vol 25 (10) ◽

pp. 4061-4074 ◽

Cited By ~ 134

Author(s):

Wei-Yi Lin ◽

Teng-Kuei Huang ◽

Tzyy-Jen Chiou

Keyword(s):

Plasma Membrane ◽

Nitrogen Limitation ◽

Phosphate Homeostasis ◽

Phosphate Transporters

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ArabidopsisFerritin 1 (AtFer1) Gene Regulation by the Phosphate Starvation Response 1 (AtPHR1) Transcription Factor Reveals a Direct Molecular Link between Iron and Phosphate Homeostasis

Journal of Biological Chemistry ◽

10.1074/jbc.m113.482281 ◽

2013 ◽

Vol 288 (31) ◽

pp. 22670-22680 ◽

Cited By ~ 75

Author(s):

Marc Bournier ◽

Nicolas Tissot ◽

Stéphane Mari ◽

Jossia Boucherez ◽

Eric Lacombe ◽

...

Keyword(s):

Gene Regulation ◽

Transcription Factor ◽

Phosphate Starvation ◽

Phosphate Homeostasis ◽

Starvation Response ◽

Phosphate Starvation Response

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Faculty Opinions recommendation of A phosphate starvation response regulator Ta-PHR1 is involved in phosphate signalling and increases grain yield in wheat.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.725728667.793509077 ◽

2015 ◽

Author(s):

Luis Herrera-Estrella

Keyword(s):

Grain Yield ◽

Response Regulator ◽

Phosphate Starvation ◽

Starvation Response ◽

Phosphate Starvation Response

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Actin-membrane interaction in fibroblasts: what proteins are involved in this association?

The Journal of Cell Biology ◽

10.1083/jcb.99.1.95s ◽

1984 ◽

Vol 99 (1) ◽

pp. 95s-103s ◽

Cited By ~ 57

Author(s):

P Mangeat ◽

K Burridge

Keyword(s):

Plasma Membrane ◽

Actin Filaments ◽

Stress Fiber ◽

Membrane Interaction ◽

Microfilament Bundles ◽

The Family ◽

Form Part ◽

Membrane Attachment ◽

A Chain ◽

And Function

In this review we discuss some of the proteins for which a role in linking actin to the fibroblast plasma membrane has been suggested. We focus on the family of proteins related to erythrocyte spectrin, proteins that have generally been viewed as having an organization and a function in actin-membrane attachment similar to those of erythrocyte spectrin. Experiments in which we precipitated the nonerythrocyte spectrin within living fibroblasts have led us to question this supposed similarity of organization and function of the nonerythrocyte and erythrocyte spectrins. Intracellular precipitation of fibroblast spectrin does not affect the integrity of the major actin-containing structures, the stress fiber microfilament bundles. Unexpectedly, however, we found that the precipitation of spectrin results in a condensation and altered distribution of the vimentin class of intermediate filaments in most cells examined. Although fibroblast spectrin may have a role in the attachment of some of the cortical, submembranous actin, it is surprising how little the intracellular immunoprecipitation of the spectrin affects the cells. Several proteins have been found concentrated at the ends of stress fibers, where the actin filaments terminate at focal contacts. Two of these proteins, alpha-actinin and fimbrin, have properties that suggest that they are not involved in the attachment of the ends of the bundles to the membrane but are more probably involved in the organization and cross-linking of the filaments within the bundles. On the other hand, vinculin and talin are two proteins that interact with each other and may form part of a chain of attachments between the ends of the microfilament bundles and the focal contact membrane. Their role in this attachment, however, has not been established and further work is needed to examine their interaction with actin and to identify any other components with which they may interact, particularly in the plasma membrane.

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Impact of Membrane Lipids on UapA and AzgA Transporter Subcellular Localization and Activity in Aspergillus nidulans

Journal of Fungi ◽

10.3390/jof7070514 ◽

2021 ◽

Vol 7 (7) ◽

pp. 514

Author(s):

Mariangela Dionysopoulou ◽

George Diallinas

Keyword(s):

Plasma Membrane ◽

Subcellular Localization ◽

Aspergillus Nidulans ◽

Membrane Lipids ◽

Membrane Lipid ◽

Lipid Biosynthesis ◽

Transport Kinetics ◽

Negative Effect ◽

And Function

Recent biochemical and biophysical evidence have established that membrane lipids, namely phospholipids, sphingolipids and sterols, are critical for the function of eukaryotic plasma membrane transporters. Here, we study the effect of selected membrane lipid biosynthesis mutations and of the ergosterol-related antifungal itraconazole on the subcellular localization, stability and transport kinetics of two well-studied purine transporters, UapA and AzgA, in Aspergillus nidulans. We show that genetic reduction in biosynthesis of ergosterol, sphingolipids or phosphoinositides arrest A. nidulans growth after germling formation, but solely blocks in early steps of ergosterol (Erg11) or sphingolipid (BasA) synthesis have a negative effect on plasma membrane (PM) localization and stability of transporters before growth arrest. Surprisingly, the fraction of UapA or AzgA that reaches the PM in lipid biosynthesis mutants is shown to conserve normal apparent transport kinetics. We further show that turnover of UapA, which is the transporter mostly sensitive to membrane lipid content modification, occurs during its trafficking and by enhanced endocytosis, and is partly dependent on autophagy and Hect-type HulARsp5 ubiquitination. Our results point out that the role of specific membrane lipids on transporter biogenesis and function in vivo is complex, combinatorial and transporter-dependent.

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Plasma membrane integrity in health and disease: significance and therapeutic potential

Cell Discovery ◽

10.1038/s41421-020-00233-2 ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Catarina Dias ◽

Jesper Nylandsted

Keyword(s):

Plasma Membrane ◽

Therapeutic Potential ◽

Calcium Influx ◽

Membrane Integrity ◽

Cell Types ◽

Physical Parameters ◽

Membrane Repair ◽

Plasma Membrane Integrity ◽

Repair Mechanisms ◽

And Function

AbstractMaintenance of plasma membrane integrity is essential for normal cell viability and function. Thus, robust membrane repair mechanisms have evolved to counteract the eminent threat of a torn plasma membrane. Different repair mechanisms and the bio-physical parameters required for efficient repair are now emerging from different research groups. However, less is known about when these mechanisms come into play. This review focuses on the existence of membrane disruptions and repair mechanisms in both physiological and pathological conditions, and across multiple cell types, albeit to different degrees. Fundamentally, irrespective of the source of membrane disruption, aberrant calcium influx is the common stimulus that activates the membrane repair response. Inadequate repair responses can tip the balance between physiology and pathology, highlighting the significance of plasma membrane integrity. For example, an over-activated repair response can promote cancer invasion, while the inability to efficiently repair membrane can drive neurodegeneration and muscular dystrophies. The interdisciplinary view explored here emphasises the widespread potential of targeting plasma membrane repair mechanisms for therapeutic purposes.

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