CrMAPK3 regulates the expression of iron-deficiency-responsive genes in Chlamydomonas reinhardtii.

Authors:
Xiaowen Fei
Xiaowen Fei
Institute of Tropical Bioscience and Biotechnology
China
Yajun Li
Yajun Li
Shanghai Institute of Organic Chemistry
China
Xiaodong Deng
Xiaodong Deng
Key Laboratory of Tropical Crop Biotechnology

BMC Biochem 2017 05 16;18(1). Epub 2017 May 16.

Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural Science, Key Laboratory of Tropical Crop Biotechnology, Ministry of Agriculture, Haikou, 571101, China.

Background: Under iron-deficient conditions, Chlamydomonas exhibits high affinity for iron absorption. Nevertheless, the response, transmission, and regulation of downstream gene expression in algae cells have not to be investigated. Considering that the MAPK pathway is essential for abiotic stress responses, we determined whether this pathway is involved in iron deficiency signal transduction in Chlamydomonas.

Results: Arabidopsis MAPK gene sequences were used as entry data to search for homologous genes in Chlamydomonas reinhardtii genome database to investigate the functions of mitogen-activated protein kinase (MAPK) gene family in C. reinhardtii under iron-free conditions. Results revealed 16 C. reinhardtii MAPK genes labeled CrMAPK2-CrMAPK17 with TXY conserved domains and low homology to MAPK in yeast, Arabidopsis, and humans. The expression levels of these genes were then analyzed through qRT-PCR and exposure to high salt (150 mM NaCl), low nitrogen, or iron-free conditions. The expression levels of these genes were also subjected to adverse stress conditions. The mRNA levels of CrMAPK2, CrMAPK3, CrMAPK4, CrMAPK5, CrMAPK6, CrMAPK8, CrMAPK9, and CrMAPK11 were remarkably upregulated under iron-deficient stress. The increase in CrMAPK3 expression was 43-fold greater than that in the control. An RNA interference vector was constructed and transformed into C. reinhardtii 2A38, an algal strain with an exogenous FOX1:ARS chimeric gene, to silence CrMAPK3. After this gene was silenced, the mRNA levels and ARS activities of FOX1:ARS chimeric gene and endogenous CrFOX1 were decreased. The mRNA levels of iron-responsive genes, such as CrNRAMP2, CrATX1, CrFTR1, and CrFEA1, were also remarkably reduced.

Conclusion: CrMAPK3 regulates the expression of iron-deficiency-responsive genes in C. reinhardtii.

Download full-text PDF

Source
http://dx.doi.org/10.1186/s12858-017-0081-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5434638PMC
May 2017
39 Reads

Publication Analysis

Top Keywords

mrna levels
12
fox1ars chimeric
8
iron-free conditions
8
mapk gene
8
chimeric gene
8
expression levels
8
levels genes
8
chlamydomonas reinhardtii
8
genes chlamydomonas
8
iron-deficiency-responsive genes
8
regulates expression
8
crmapk3 regulates
8
expression iron-deficiency-responsive
8
genes
7
gene
6
reinhardtii
6
expression
6
mapk
5
crmapk3
5
levels
5

References

(Supplied by CrossRef)
Article in Plant Cell Physiol
XW Fei et al.
Plant Cell Physiol 2007
Article in BMC Genomics
KT Mohanta et al.
BMC Genomics 2015
Article in J Biol Chem
MAG Besteiro et al.
J Biol Chem 2013
Article in FEBS J
CJ Caunt et al.
FEBS J 2013
Article in Annu Rev Plant Biol
MC Rodriguez et al.
Annu Rev Plant Biol 2010
Article in Trends Plant Sci
H Nakagami et al.
Trends Plant Sci 2005
Article in FEBS Lett
T Mizoguchi et al.
FEBS Lett 1993
Article in Plant Physiol
D Lieberherr et al.
Plant Physiol 2005
Article in Plant Mol Biol
M Lalle et al.
Plant Mol Biol 2005
Article in Plant Mol Biol
D Takezawa et al.
Plant Mol Biol 1999
Article in Plant Cell
M Knetsch et al.
Plant Cell 1996

Similar Publications