RiceFOX: a database of Arabidopsis mutant lines overexpressing rice full-length cDNA that contains a wide range of trait information to facilitate analysis of gene function.

Identification of gene function is important not only for basic research but also for applied science, especially with regard to improvements in crop production. For rapid and efficient elucidation of useful traits, we developed a system named FOX hunting (Full-length cDNA Over-eXpressor gene hunting) using full-length cDNAs (fl-cDNAs). A heterologous expression approach provides a solution for the high-throughput characterization of gene functions in agricultural plant species. Since fl-cDNAs contain all the information of functional mRNAs and proteins, we introduced rice fl-cDNAs into Arabidopsis plants for systematic gain-of-function mutation. We generated >30,000 independent Arabidopsis transgenic lines expressing rice fl-cDNAs (rice FOX Arabidopsis mutant lines). These rice FOX Arabidopsis lines were screened systematically for various criteria such as morphology, photosynthesis, UV resistance, element composition, plant hormone profile, metabolite profile/fingerprinting, bacterial resistance, and heat and salt tolerance. The information obtained from these screenings was compiled into a database named 'RiceFOX'. This database contains around 18,000 records of rice FOX Arabidopsis lines and allows users to search against all the observed results, ranging from morphological to invisible traits. The number of searchable items is approximately 100; moreover, the rice FOX Arabidopsis lines can be searched by rice and Arabidopsis gene/protein identifiers, sequence similarity to the introduced rice fl-cDNA and traits. The RiceFOX database is available at http://ricefox.psc.riken.jp/.

Systematic approaches to using the FOX hunting system to identify useful rice genes.

Ectopic gene expression, or the gain-of-function approach, has the advantage that once the function of a gene is known the gene can be transferred to many different plants by transformation. We previously reported a method, called FOX hunting, that involves ectopic expression of Arabidopsis full-length cDNAs in Arabidopsis to systematically generate gain-of-function mutants. This technology is most beneficial for generating a heterologous gene resource for analysis of useful plant gene functions. As an initial model we generated more than 23,000 independent Arabidopsis transgenic lines that expressed rice fl-cDNAs (Rice FOX Arabidopsis lines). The short generation time and rapid and efficient transformation frequency of Arabidopsis enabled the functions of the rice genes to be analyzed rapidly. We screened rice FOX Arabidopsis lines for alterations in morphology, photosynthesis, element accumulation, pigment accumulation, hormone profiles, secondary metabolites, pathogen resistance, salt tolerance, UV signaling, high light tolerance, and heat stress tolerance. Some of the mutant phenotypes displayed by rice FOX Arabidopsis lines resulted from the expression of rice genes that had no homologs in Arabidopsis. This result demonstrated that rice fl-cDNAs could be used to introduce new gene functions in Arabidopsis. Furthermore, these findings showed that rice gene function could be analyzed by employing Arabidopsis as a heterologous host. This technology provides a framework for the analysis of plant gene function in a heterologous host and of plant improvement by using heterologous gene resources.

Clinical investigation: Reliability and validity of the Japanese version of quality of life radiation therapy instrument (QOL-RTI) for Japanese patients with head and neck malignancies.

PURPOSE: To evaluate the reliability and validity of the Japanese translation of Quality of Life Radiation Therapy Instrument (QOL-RTI) and the head and neck module (H&N) for Japanese patients being treated with radiotherapy for head and neck malignancies. MATERIALS & METHODS: The QOL-RTI/H&N was translated into Japanese by a preliminary QOL research working group of JASTRO and was used in this clinical trial. From 1998 to 2001, 70 patients with head and neck malignancies for whom radical radiotherapy was planned were entered into this study. Patients were requested to answer the questions before radiotherapy at baseline, twice during week 4 of therapy (for test-retest reliability), at the end of treatment, and 3 months, 6 months, 1 year and 2 years from the beginning of radiotherapy. Internal consistency was assessed by Cronbach's alpha coefficient. Validity was assessed by comparing the results with EORTC-QLQ-C30 and with QOL questionnaire for cancer patients treated with anticancer drugs (QOL-ADC). Patient compliance and test sensitivity were also analyzed. RESULTS: Cronbach's alpha coefficient was 0.79 to 0.93 depending on the time point for the evaluation. Test-retest reliability was acceptable, with a Pearson coefficient of 0.83 for QOL-RTI and 0.92 for H&N module. Compliance with this scheme was 98.2%. The QOL-RTI was sensitive enough to detect significant changes in the QOL score during and after the course of radiotherapy. Agreement with the EORTC-C30 was good with a high Pearson correlation coefficient of 0.648 and that with QOL-ADC was also good with a coefficient of 0.566. The factors analyzed consisted of 11 functional/health-oriented questions, 5 emotional/ psychological, 5 socio-economic/ family and 2 general. CONCLUSION: The Japanese version of QOL-RTI with H&N module was found to be reliable and sensitive enough to evaluate variation of QOL in patients with head and neck malignancies during and after radiotherapy.