Steiner, E. - Institute of Plant Sciences and Genetics in Agriculture, Hebrew University of Jerusalem, Rehovot, 7610001, Israel
Israeli, A.- Institute of Plant Sciences and Genetics in Agriculture, Hebrew University of Jerusalem, Rehovot, 7610001, Israel
Gupta, R. - Department of Plant Pathology and Weed Research, Plant Protection Institute, Agricultural Research Organization, The Volcani Center, Rishon LeZion, 7505101, Israel.
Shwartz, I.- Institute of Plant Sciences and Genetics in Agriculture, Hebrew University of Jerusalem, Rehovot, 7610001, Israel
Nir, I. - Institute of Plant Sciences and Genetics in Agriculture, Hebrew University of Jerusalem, Rehovot, 7610001, Israel; Department of Biology, Stanford University, Stanford, CA 94305, United States.
Leibman-Markus, M. - Department of Plant Pathology and Weed Research, Plant Protection Institute, Agricultural Research Organization, The Volcani Center, Rishon LeZion, 7505101, Israel.
Tal, L. - Department of Plant and Environmental Science, Weizmann Institute of Science, Rehovot, 7610001, Israel; Department of Plant Biology, University of California – Davis, Davis, CA 95616, United States.
Farber, M. - Institute of Plant Sciences and Genetics in Agriculture, Hebrew University of Jerusalem, Rehovot, 7610001, Israel.
Amsalem, Z. - Department of Plant and Environmental Science, Weizmann Institute of Science, Rehovot, 7610001, Israel.
Ori, N. - Institute of Plant Sciences and Genetics in Agriculture, Hebrew University of Jerusalem, Rehovot, 7610001, Israel.
Müller, B. - Leibniz-Institut Für Pflanzengenetik Und Kulturpflanzenforschung (IPK), Corrensstraße 3, Seeland, 06466, Germany; Microsynth AG, Schützenstrasse 15, Balgach, 9436, Switzerland.
Bar, M. - Department of Plant Pathology and Weed Research, Plant Protection Institute, Agricultural Research Organization, The Volcani Center, Rishon LeZion, 7505101, Israel.

Background: Hormones are crucial to plant life and development. Being able to follow the plants hormonal response to various stimuli and throughout developmental processes is an important and increasingly widespread tool. The phytohormone cytokinin (CK) has crucial roles in the regulation of plant growth and development.
Results: Here we describe a version of the CK sensor Two Component signaling Sensor (TCS), referred to as TCSv2. TCSv2 has a different arrangement of binding motifs when compared to previous TCS versions, resulting in increased sensitivity in some examined tissues. Here, we examine the CK responsiveness and distribution pattern of TCSv2 in arabidopsis and tomato.
Conclusions: The increased sensitivity and reported expression pattern of TCSv2 make it an ideal TCS version to study CK response in particular hosts, such as tomato, and particular tissues, such as leaves and flowers.