c-Jun N-terminal kinase 1 (JNK1) phosphorylates OTX2 transcription factor that regulates early retinal development.

BACKGROUND: The transcription factor orthodenticle homeobox 2 (OTX2) has critical functions in brain and eye development, and its mutations in humans are related to retinal diseases, such as ocular coloboma and microphthalmia. However, the regulatory mechanisms of OTX2 are poorly identified. OBJECTIVE: The identification of JNK1 as an OTX2 regulatory protein through the protein interaction and phosphorylation. METHODS: To identify the binding partner of OTX2, we performed co-immunoprecipitation and detected with a pooled antibody that targeted effective kinases. The protein interaction between JNK1 and OTX2 was identified with the co-immunoprecipitation and immunocytochemistry. In vivo and in vitro kinase assay of JNK1 was performed to detect the phosphorylation of OTX2 by JNK1. RESULTS: JNK1 directly interacted with OTX2 through the transactivation domain at the c-terminal region. The protein-protein interaction and co-localization between JNK1 and OTX2 were further validated in the developing P0 mouse retina. In addition, we confirmed that the inactivation of JNK1 K55N mutant significantly reduced the JNK1-mediated phosphorylation of OTX2 by performing an immune complex protein kinase assay. CONCLUSION: c-Jun N-terminal kinase 1 (JNK1) phosphorylates OTX2 transcription factor through the protein-protein interaction.

Association between Falls and Nutritional Status of Community-Dwelling Elderly People in Korea.

BACKGROUND: Malnutrition is a well-known risk factor of falls, although studies examining the association between nutritional status and falls are rare. We aimed to investigate the association between nutritional status and falls according to gender among Korean older adults. METHODS: The study included 10,675 participants (4,605 men and 6,070 women) aged 65 years and older and used data from the 2011 Survey of Living Conditions and Welfare Needs of Korean Older Persons. Nutritional status of the participants was assessed using the Nutritional Screening Initiative checklist, and the participants were categorized into the following groups: "good," "moderate nutritional risk," and "high nutritional risk." Odds ratios (OR) of fall risk in the above groups based on gender were evaluated using multivariate logistic regression analyses. RESULTS: Fallers in both genders showed significant association with older age, lower household income, inadequate exercise, and poor nutritional status compared with non-fallers. Considering the good nutritional status group as the reference group, the high nutritional risk group showed a higher risk of falls in men (OR, 1.59; 95% confidence interval [CI], 1.26-1.99); both moderate and high nutritional risk groups showed a higher risk of falls after adjusting for confounding factors in women (OR, 1.39; 95% CI, 1.19-1.62 and OR, 1.90; 95% CI, 1.61-2.24, respectively). CONCLUSION: The risk of falls was associated with poor nutritional status, and statistical significance of the association between nutritional status and falls was stronger in women than in men.