Calcineurin B-like 3 calcium sensor associates with and inhibits 5′-methylthioadenosine nucleosidase 2 in Arabidopsis. (September 2015)

• Record Type: Journal Article
• Authors: Ok, Sung Han; Cho, Joo Hyuk; Oh, Seung-Ick; Choi, Mi Na; Ma, Jae-Yeon; Shin, Jeong-Sheop; Kim, Kyung-Nam
• Is Part Of: Plant science. Volume 238(2015:Sep.)
• Page Start: 228
• Page End: 240
• Publication Date: 2015-09
• Subjects: CBLs calcineurin B-like proteins -- CIPKs CBL-interacting protein kinases -- MTANs 5′-methylthioadenosine nucleosidases -- CaMs calmodulins -- CMLs CaM-like proteins -- CDPKs Ca2+-dependent protein kinases -- YFP yellow fluorescence protein -- CFP cyan fluorescence protein -- BiFC bimolecular fluorescence complementation -- MTA 5′-methylthioadenosine -- MTR 5′-methylthioribose -- SAM S-adenosyl-L-methionine -- NA nicotianamine -- PA polyamine -- RT-PCR reverse transcription PCR -- GST glutathione S-transferase -- CaMV cauliflower mosaic virus; Calcium signaling -- CBL -- CIPK -- MTAN -- Arabidopsis; Botany -- Periodicals; Botanique -- Périodiques; 580
• DOI: 10.1016/j.plantsci.2015.06.016
• Languages: English
• ISSNs: 0168-9452

Abstract

Highlights: CBL3 can associate with the AtMTAN family besides the CIPK family members. CBL2 and CBL6 can also interact with AtMTAN1, but not with AtMTAN2. CBL3-AtMTAN association occurs in a Ca 2+ -dependent manner. CBL3 inhibits the enzymatic activity of the AtMTAN proteins. CBL3 disrupts homodimerization of AtMTAN proteins. Abstract: Calcineurin B-like (CBL) proteins constitute a unique family of calcium sensor relays in plants. It is well known that CBLs detect the calcium signals elicited by a variety of abiotic stresses and relay the information to a group of serine/threonine protein kinases called CBL-interacting protein kinases (CIPKs). In this study, we found that a few CBL members can also target another group of enzymes 5′-methylthioadenosine nucleosidases (MTANs), which are encoded by two genes in Arabidopsis, AtMTAN1 and AtMTAN2 . In the yeast two-hybrid system, AtMTAN1 interacted with multiple CBL members such as CBL2, CBL3 and CBL6, whereas AtMTAN2 associated exclusively with CBL3. We further demonstrated that the CBL3-AtMTAN2 association occurs in a calcium-dependent manner, which results in a significant decrease in the enzyme activity of the AtMTAN2 protein. Taken together, these results clearly indicate that the CBL family can target at least two distinct groups of enzymes (CIPKs and MTANs), conferring an additional level of complexity on the CBL-mediated signaling networks. In addition, our finding also provides a novel molecular mechanism by which calcium signals are transduced to alter metabolite profiles in plants.