A novel GRAS protein gene MtSymSCL1 plays a role in regulating nodule number in Medicago truncatula
Legume-rhizobium symbiosis requires the expression of a series of plant genes playing roles in nodulation signaling that leads to the formation of functional nodules. A few plant-specific GRAS proteins have been shown to be involved in early nodulation signaling. Here, we isolated a novel SCARECROW...
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Published in | Plant growth regulation Vol. 71; no. 1; pp. 77 - 92 |
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Main Authors | , |
Format | Journal Article |
Language | English |
Published |
Dordrecht
Springer Netherlands
01.09.2013
Springer Nature B.V |
Subjects | |
Online Access | Get full text |
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Summary: | Legume-rhizobium symbiosis requires the expression of a series of plant genes playing roles in nodulation signaling that leads to the formation of functional nodules. A few plant-specific GRAS proteins have been shown to be involved in early nodulation signaling. Here, we isolated a novel
SCARECROW
-like GRAS protein gene,
MtSymSCL1
, from the model legume
Medicago truncatula
.
MtSymSCL1
has unique gene and protein domain structures, and its homologs are identified from various plant species. Phylogenetic analysis showed that MtSymSCL1 could be classified into a novel subclass in the GRAS protein family.
MtSymSCL1
transcript accumulated highly in nodulated roots at 14 days after inoculation of
Sinorhizobium meliloti
. Translationally fused MtSymSCL1-GFP expressed from a viral or the native promoter was co-localized with nuclear localization signal-fused RFP in leaf mesophyll protoplasts
, Agrobacterium rhizogenes
-transformed hairy root cells, and epidermal cells of nodules that developed on the transformed roots. Unlike
SCARECROW
of
Arabidopsis
, however, RNA silencing of
MtsymSCL1
did not affect root growth, nor root hair curling and infection thread growth. Nevertheless,
MtSymSCL1
-silenced roots developed significantly fewer nodules than
GUS
-silenced roots, as shown by replicated nodulation assay with pot- or agar plate-grown plants. The structure of
MtSymSCL1
-silenced root nodules appeared similar to that of the wild type, as shown by sectioned nodules stained with green fluorescent dye. Together, these results suggest that
MtSymSCL1
plays a role in regulating nodule number during legume-rhizobium symbiosis. |
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Bibliography: | ObjectType-Article-2 SourceType-Scholarly Journals-1 ObjectType-Feature-1 content type line 23 |
ISSN: | 0167-6903 1573-5087 |
DOI: | 10.1007/s10725-013-9814-7 |