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Unlike animals, plants are sessile organisms and have evolved to tolerate a constantly changing environment. They have developed a complex signaling network to perceive and adapt to a wide range of stress conditions. Calcium signatures generated after stress conditions can be decoded and modulated by calcium binding proteins, which relay the signal by activating kinases, transcription factor or directly acting at promoters of effector genes. Calcineurin-B like proteins (CBLs) are calcium sensor proteins that relay calcium signatures by binding and activating a group of protein kinases known as CBL-interacting protein kinases (CIPKs). In plants CIPKs and CBLs are usually involved in ABA signaling, drought, salinity and cold responses, auxin transport and sugar signaling. Although some CIPK/CBL pathways have been described and functionally studied in Arabidopsis, little is known in sugarcane. RNA blot assays have identified a sugarcane CIPK gene, named ScCIPK8, that is more expressed in leaves of 9 months-old sugarcane plants with low Brix content, compared to plants with high Brix content. To understand the role of this gene we produced transgenic sugarcane plant using an anti-sense construct. Leaves of transgenic sugarcane plants in which ScCIPK8 gene was silenced showed higher sucrose levels. Additionally, previous microarray experiments have shown that ScCIPK8 gene expression is up-regulated in leaves of sugarcane plants submitted to drought stress under greenhouse conditions. These results indicate a role of ScCIPK8 protein on sugar metabolism and stress responses. In order to shed light on the pathways in which ScCIPK8 protein may be involved, we used yeast-two hybrid assays to identify proteins that could interact with it in sugarcane. We found that ScCIPK8 interacts with three sugarcane CBLs (ScCBL1, ScCBL3 and ScCBL6), a PP2C protein and a MYC2 transcription factor. These results indicate that ScCIPK8 may play a pivotal role on a complex protein-protein interaction network that might act in the regulation of sucrose metabolism and responses to drought.