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Title: Regulating cellular trace metal economy in algae

Abstract

As indispensable protein cofactors, Fe, Mn, Cu and Zn are at the center of multifaceted acclimation mechanisms that have evolved to ensure extracellular supply meets intracellular demand. In starting with selective transport at the plasma membrane and ending in protein metalation, metal homeostasis in algae involves regulated trafficking of metal ions across membranes, intracellular compartmentalization by proteins and organelles, and metal-sparing/recycling mechanisms to optimize metal-use efficiency. Overlaid on these processes are additional circuits that respond to the metabolic state as well as to the prior metal status of the cell. Here, we focus on recent progress made toward understanding the pathways by which the single-celled, green alga Chlamydomonas reinhardtii controls its cellular trace metal economy. We also compare these mechanisms to characterized and putative processes in other algal lineages. Photosynthetic microbes continue to provide insight into cellular regulation and handling of Cu, Fe, Zn and Mn as a function of the nutritional supply and cellular demand for metal cofactors. We found that new experimental tools such as RNA-Seq and subcellular metal imaging are bringing us closer to a molecular understanding of acclimation to supply dynamics in algae and beyond.

Authors:
 [1]; ORCiD logo [2]
  1. Brookhaven National Lab. (BNL), Upton, NY (United States). Biology Dept.
  2. Univ. of California, Los Angeles, CA (United States). Dept. of Chemistry and Biochemistry, Inst. for Genomics and Proteomics
Publication Date:
Research Org.:
Brookhaven National Laboratory (BNL), Upton, NY (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Biological and Environmental Research (BER) (SC-23)
OSTI Identifier:
1372451
Report Number(s):
BNL-114050-2017-JA
Journal ID: ISSN 1369-5266
Grant/Contract Number:
SC00112704; FD02-04ER15529; GM42143
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Current Opinion in Plant Biology
Additional Journal Information:
Journal Volume: 39; Journal Issue: C; Journal ID: ISSN 1369-5266
Publisher:
Elsevier
Country of Publication:
United States
Language:
English
Subject:
59 BASIC BIOLOGICAL SCIENCES; acidocalcisome; polyphosphate; flavodoxin; diatoms; transferrin; iron; copper; zinc

Citation Formats

Blaby-Haas, Crysten E., and Merchant, Sabeeha S. Regulating cellular trace metal economy in algae. United States: N. p., 2017. Web. doi:10.1016/j.pbi.2017.06.005.
Blaby-Haas, Crysten E., & Merchant, Sabeeha S. Regulating cellular trace metal economy in algae. United States. doi:10.1016/j.pbi.2017.06.005.
Blaby-Haas, Crysten E., and Merchant, Sabeeha S. 2017. "Regulating cellular trace metal economy in algae". United States. doi:10.1016/j.pbi.2017.06.005.
@article{osti_1372451,
title = {Regulating cellular trace metal economy in algae},
author = {Blaby-Haas, Crysten E. and Merchant, Sabeeha S.},
abstractNote = {As indispensable protein cofactors, Fe, Mn, Cu and Zn are at the center of multifaceted acclimation mechanisms that have evolved to ensure extracellular supply meets intracellular demand. In starting with selective transport at the plasma membrane and ending in protein metalation, metal homeostasis in algae involves regulated trafficking of metal ions across membranes, intracellular compartmentalization by proteins and organelles, and metal-sparing/recycling mechanisms to optimize metal-use efficiency. Overlaid on these processes are additional circuits that respond to the metabolic state as well as to the prior metal status of the cell. Here, we focus on recent progress made toward understanding the pathways by which the single-celled, green alga Chlamydomonas reinhardtii controls its cellular trace metal economy. We also compare these mechanisms to characterized and putative processes in other algal lineages. Photosynthetic microbes continue to provide insight into cellular regulation and handling of Cu, Fe, Zn and Mn as a function of the nutritional supply and cellular demand for metal cofactors. We found that new experimental tools such as RNA-Seq and subcellular metal imaging are bringing us closer to a molecular understanding of acclimation to supply dynamics in algae and beyond.},
doi = {10.1016/j.pbi.2017.06.005},
journal = {Current Opinion in Plant Biology},
number = C,
volume = 39,
place = {United States},
year = 2017,
month = 6
}

Journal Article:
Free Publicly Available Full Text
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