Runt related transcription factors (RUNX), a family of well-known transcription factors, play key regulatory roles in diverse biological processes, such as proliferation, differentiation, and DNA repair. Of RUNX family, RUNX3 is the least well characterized of the three family members. Nevertheless, the role of RUNX3 as a key regulator in essential biological pathways has been reported and inactivation of RUNX3 leads to a variety of disease, such as cancer, via regulation of Wnt signaling and K-ras mutations in many mammalian tissues. Recent studies using RUNX3-deficient cells and mice revealed an association with hematopoiesis and hypersensitivity to granulocytecolony stimulating factor. Nevertheless, protein dynamics associated with RUNX3 remain poorly understood. In the present study, we performed a large-scale protein study from Runx3 knockout (KO) mouse embryonic stem cells (mESC) using a stable isotope labeling by amino acids (SILAC)-based quantitative proteomics approach. The results showed that 67 proteins were significantly up and downregulated after Runx3 KO. Bioinformatic analyses that revealed that these proteins have diverse biological functions, such as substances transport and cellular structure. Thus, our results enhance our current understanding of the function of RUNX3 in mESCs and suggest potential roles for RUNX proteins in diverse diseases. Additionally, our results can be used as a database to help us understand the mechanism of action of RUNX3.

To examine the differential expression of proteins during the cycling (70～80% confluences) and G0/G1 (full confluences) phases in porcine fetal fibroblast cells, we used a global proteomics approach by 2‐D gel electrophoresis (2‐DE) and MALDI‐TOF‐MS. Cycling cell were harvested at approximately 70% to 80% confluent state while cells in G0/G1 phase were recovered after maintenance of a confluent state for 48 hr. Cellular proteins with isoelectric points ranging between 3.0～10.0, were analyzed by 2‐DE with 2 replicates of each sample. A total of approximately 700 spots were detected by 2‐D gels stained with Coomassie brilliant blue. On comparing the cell samples obtained from the cycling and G0/G1 phases, a total of 13 spots were identified as differentially expressed proteins, of which 8 spots were up‐regulated in the cycling cell and 5 were up‐regulated in the G0/G1 phase. Differentially expressed proteins included K3 keratin, similar to serine protease 23 precursor, protein disulfide‐isomerase A3, microsomal protease ER‐60, alpha‐actinin‐2, and heat‐shock protein 90 beta. The identified proteins were grouped on the basis of their basic functions such as molecular binding, catabolic, cell growth, and transcription regulatory proteins. Our results show expression profiles of key proteins in porcine fetal fibroblast cells during different cell cycle status.

We examined the effects of cadmium exposure and various temperature stress on the expression of Pardosa astrigera heat shock protein 70 (HSP70). To do this, P. astrigera HSP70 gene was cloned and its sequence determined. Female spiders collected from non-contaminated region were exposed to 40mM CdCl2 for 2, 4 and 6 weeks by dietary uptake. At the end of every 2, 4 and 6 weeks of exposure, a batch of 5 spiders was collected and total RNA was extracted from each batch of whole bodies. Female spiders were also exposed to different temperatures (20, 25, 30 and 35℃) for 3h and RNA extracted likewise. Transcription profiles of HSP70 in response to cadmium and temperature were determined by quantitative real-time PCR using 18S rRNA as reference gene for data normalization. HSP70 transcription gradually increased during 2,4 and 6 weeks of exposure to cadmium. In particular, the expression level at 6-week exposure was 3.4-fold higher than that of untreated control. In the temperature response, an increased expression of HSP70 was also observed as temperature increased up to 30℃ and then slightly decreased at 35℃. The expression level at 30℃ was 2.3-fold higher than that of 25℃. Taken together, HSP70 gene appears to be up-regulated by general stress factors including cadmium exposure and temperature increase.

Seed storage proteins are used as carbon and nitrogen sources for the nutritional improvement of seeds. Since the composition of proteins from the Korean cultivars of proso millet is unknown, this study was conducted to obtain a reference map of millet seed proteins and identify the functional characteristics of the identified proteins. Proteins extracted from proso millet seeds of various cultivars were investigated using proteomic techniques such as 2-D electrophoresis coupled with mass fingerprinting; 1152 (differentially expressed) protein spots were detected on the 2-D gels. Among them, 26 reproducible protein spots were analyzed using matrix-assisted laser desorption/ionization time-of-flight/time-of-flight mass spectrometry. Out of the 26 proteins, 2 proteins were upregulated in all the millet cultivars, while 13 proteins were upregulated and 11 proteins were downregulated in 2 cultivars. Abundance of most of the identified protein species associated with polysaccharide and starch metabolism, transcription, and pathogenesis was significantly enhanced, while that of other protein species involved in glycolysis, stress response, and transduction was severely reduced. Taken together, the results suggest that the differential expression of the proteins from the four millet cultivars may be cultivar-specific. By conducting a proteomic investigation of millet seeds from different cultivars, we sought to better understand the functional categorization of individual proteins on the basis of their molecular functions. We believe that the identified proteins may help in investigating genetic variations in millet cultivars.

Single seeds of common buckwheat cultivar Suwon No. 1 when subjected to SDS-PAGE revealed very high polymorphism. High variation existed for protein or protein subunits with molecular weight 54-47kDa, 45-25kDa and 16-11kDa. The electrophoregram showed variation for globulin as well as other protein fractions. About 300 proteins were separated by two-dimensional electrophoresis in common buckwheat (Fagopyrum esculentum Moench.) seed. Seed maturation is a dynamic and temporally regulated phase of seed development that determines the composition of storage proteins reserves in mature seeds. Buckwheat seeds from 5, 10, 15, 20, and 25 days after pollination and matured stage were used for the analysis. This led to the establishment of high-resolution proteome reference maps, expression profiles of 48 spots. It was identified 48 proteins from MALDI-TOF/MS analysis of wild buckwheat seed storage proteins. The 48 proteins were found identical or similar to those of proteins reported in buckwheat and other plants; it is belonging to 9 major functional categories including seed storage proteins, stress/defense response, protein synthesis, photosynthesis, allergy proteins, amino acid, enzyme, metabolism, and miscellaneous. It appears that the major allergenic storage protein separated played the important role in buckwheat breeding and biochemical characterization.

본 연구는 혀의 분얼최성기의 관수스트레스 시 탁도(청수, 반탁수, 탁수) 및 관수시간에 따라 반응하는 단백질, 지방산 조성 및 지질과산화(malodialdehyde)를 정량하여 관수에 따른 생육장해 및 그 작용기작을 구명하여, 관수에 따른 생화학적 대사의 기초자료를 제공하고자 실시되었다. 관수스트레스에 의해 가용성단백질은 약 20%가 감소하였다. 특히 탁도가 높고 관수시간이 경과할수록 급격히 감소하였으며, 관수 36시간부터 감소량이 크게 나타났다. 단백질 전기영 동패턴은 관수스트레스에 따라 생성이나 소멸한 펩타이드는 없었으나 약 53Kd부위의 폴리펩타이드는 관수초기부터 함량이 증가하였고, 약 28Kd는 48시간, 54시간에서만 함량이 증가하였다. 관수스트레스에 의한 지질의 과산화정도는 약 150%가 증가하였고, 탁도처리에서 청수와 반탁수간의 차이는 작은 경향이었지만, 관수 60시간에서 약 160-180%가 증가하였다. 그러나 탁수에서는 관수초기부터 malondialdehyde함량이 높았고, 36시간이후부터는 약 190-200%로 급격히 증가하였다. Catalase는 탁도가 높고 처리시간이 경과할수록 활성은 급격히 증가하였다. 관수 48시간을 기준으로 catalase 활성변화가 크게 나타났다. 지방산조성의 변화는 포화지방산의 조성비율은 증가하고 불포화지방산은 감소하였다. 특히 불포화지방산 중 monounsaturated은 증가하였고 polyunsaturated의 상대적인 조성비율은 감소하였다. Double bond index는 탁도가 높을수록 관수기간이 경과할수록 감소폭은 커서 불포화정도가 떨어짐을 나타냈다.