Over the past decade various approaches have been used to increase the expression level of recombinant proteins in plants. One successful approach has been to target proteins to specific subcellular sites/compartments of plant cells, such as the chloroplast. In the study reported here, hyperthermostable endoglucanase Cel5A was targeted into the chloroplasts of tobacco plants via the N-terminal transit peptide of nuclear-encoded plastid proteins. The expression levels of Cel5A transgenic lines were then determined using three distinct transit peptides, namely, the light-harvesting chlorophyll a/b-binding protein (CAB), Rubisco small subunit (RS), and Rubisco activase (RA). RS:Cel5A transgenic lines produced highly stable active enzymes, and the protein accumulation of these transgenic lines was up to 5.2% of the total soluble protein in the crude leaf extract, remaining stable throughout the life cycle of the tobacco plant. Transmission election microscopy analysis showed that efficient targeting of Cel5A protein was under the control of the transit peptide.

One of the limiting factors in the production of recombinant proteins in transgenic plants is the low level of protein accumulation. A strategy was investigated for a high level of protein accumulation in plant cells. A fungal xylanase encoded by XYLII of Trichoderma reesei was chosen as the model protein because xylanases have a high potential for applications in environment-related technologies. Xylanase was expressed in the cytosol or targeted either to chloroplasts or peroxisomes alone, or to both organelles simultaneously. When xylanase was targeted to both chloroplasts and peroxisomes simultaneously the amount of xylanase accumulated was 160% of that in chloroplasts alone and 240% of that in peroxisomes alone although the transcript levels were similar among these constructs. The growth stage of the transgenic plants also affected the total amount of xylanase; the highest level of accumulation occurred at the time of flowering. This study provides genetic and biochemical data demonstrating that a high level of protein accumulation in transgenic plants can be obtained by targeting a protein to both chloroplasts and peroxisomes at the same time.

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An ECG and tri-axial accelerometer signal monitoring and analysis method for the homecare of elderly persons or patients, using wireless sensors technology was design and implemented. This paper presents a prototype of wellness monitoring system capable of recording, and analyzing continuous ECG and accelerometer data received from the human body. The system provides an application for recording activities, events and potentially important medical symptoms. The ECG features are used to detect life-threatening arrhythmias, with an emphasis on the software for analyzing the P-wave, QRS complex, and T-wave in ECG signals at server connected to base station which is receiving data from the wireless sensor on the patient body. Activity such as walking and running are detected from the body movements recorded by the accelerometer sensor. IEEE802.15.4 is used for wireless communication between sensor and base station. If any abnormality occurs at server then the alarm condition sends to the doctor' Personal Digital Assistant (PDA).