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Abstract The precise regulation of stem cells in the shoot apical meristems (SAMs) involves the function of the homeodomain transcription factor (TF)‐WUSCHEL (WUS). WUS has been shown to move from the site of production‐the rib‐meristem (RM), into overlaying cells of the central zone (CZ), where it specifies stem cells and also regulates the transcription ofCLAVATA3 (CLV3). The secreted signalling peptide CLV3 activates a receptor kinase signalling that restrictsWUStranscription and also regulates the nuclear gradient of WUS by offsetting nuclear export. WUS has been shown to regulate bothCLV3levels and spatial activation, restricting its expression to a few cells in the CZ. The HAIRY MERISTEM (HAM), a GRASS‐domain class of TFs expressed in the RM, has been shown to physically interact with WUS and regulateCLV3expression. However, the mechanisms by which this interaction regulatesCLV3expression non‐cell autonomously remain unclear. Here, we show that HAM function is required for regulating the WUS protein stability, and theCLV3expression responds to altered WUS protein levels inhammutants. Thus, HAM proteins non‐cell autonomously regulatesCLV3expression.
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Non-active Site Residue in Loop L4 Alters Substrate Capture and Product Release in d -Arginine Dehydrogenase
- Award ID(s):
- 2018144
- PAR ID:
- 10397402
- Publisher / Repository:
- American Chemical Society
- Date Published:
- Journal Name:
- Biochemistry
- Volume:
- 62
- Issue:
- 5
- ISSN:
- 0006-2960
- Page Range / eLocation ID:
- p. 1070-1081
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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