The conventional protein chromatography technique was adopted to purify the antifreeze proteins (AFPs) from the leaves of Ammopiptanthus mongolicus (Maxim.) Cheng f. Two bands on native PAGE gel showed thermal hys...The conventional protein chromatography technique was adopted to purify the antifreeze proteins (AFPs) from the leaves of Ammopiptanthus mongolicus (Maxim.) Cheng f. Two bands on native PAGE gel showed thermal hysteresis activity, one was band B1, whose thermal hysteresis was 0.46 ℃ at 8 g/L, which showed two bands (67 kD, 21 kD) on SDS_PAGE gel; the other was B3, whose thermal hysteresis was 0.45 ℃ at 10 g/L, and it contained only a single protein (39.8 kD). Both B1 and B3 are not glycoproteins, because neither do they interact with Shiff_reagent, nor show ultraviolet characteristics of a typical glycoprotein.展开更多
Arabidopsis thaliana histone deacetylase 1 （AtHD1 or AtHDA19）, a homolog ot yeast RPD3, is a global regulator ot many physiological and developmental processes in plants. In spite of the genetic evidence for a role ...Arabidopsis thaliana histone deacetylase 1 （AtHD1 or AtHDA19）, a homolog ot yeast RPD3, is a global regulator ot many physiological and developmental processes in plants. In spite of the genetic evidence for a role of AtHD1 in plant gene regulation and development, the biochemical and cellular properties ofAtHD 1 are poorly understood. Here we report cellular localization patterns ofAtHD 1 in vivo and histone deacetylase activity in vitro. The transient and stable expression of a green fluorescent protein （GFP）-tagged AtHD1 in onion cells and in roots, seeds and leaves of the transgenic Arabidopsis, respectively, revealed that AtHD1 is localized in the nucleus presumably in the euchromatic regions and excluded from the nucleolus. The localization patterns ofAtHD 1 are different from those of AtHD2 and AtHDA6 that are involved in nucleolus formation and silencing of transgenes and repeated DNA elements, respectively. In addition, a histone deacetylase activity assay showed that the recombinant AtHD 1 produced in bacteria demonstrated a specific histone deacetylase activity in vitro. The data suggest that AtHD 1 is a nuclear protein and possesses histone deacetylase activities responsible for global transcriptional regulation important to plant growth and development.展开更多
Objective： The aim of the study was to investigate the expression and clinical significance of aldehyde dehydrogenase 1 （ALDH1） in breast cancer patients. Methods： The expression of ALDH1 protein was examined by i...Objective： The aim of the study was to investigate the expression and clinical significance of aldehyde dehydrogenase 1 （ALDH1） in breast cancer patients. Methods： The expression of ALDH1 protein was examined by immunohistochemical staining in 96 breast cancer tissues. The disease-free survival analysis of patients was evaluated based on the clinical follow-up data. Results： Expression of ALDH1 protein had significant correlations with ER, PR, and HER2 proteins （P 〈 0.05）, but had no significant correlations with age, tumor size, clinical stage, P-glycoprotein, and lymph node status （P 〉 0.05）. The 2-year disease-free survival rate of ALDHl-positive patients was lower than that of ALDHl-negative patients （P 〈 0.05）. ALDHl-positive patients undergoing chemotherapy and hormonal therapy had lower 2-year disease-free survival rate than ALDHl-negative patients （P 〈 0.05）. Conclusion： ALDH1 expression might play an important role in drug resistant, and ALDH1 may be used as a prognostic marker.展开更多
文摘The conventional protein chromatography technique was adopted to purify the antifreeze proteins (AFPs) from the leaves of Ammopiptanthus mongolicus (Maxim.) Cheng f. Two bands on native PAGE gel showed thermal hysteresis activity, one was band B1, whose thermal hysteresis was 0.46 ℃ at 8 g/L, which showed two bands (67 kD, 21 kD) on SDS_PAGE gel; the other was B3, whose thermal hysteresis was 0.45 ℃ at 10 g/L, and it contained only a single protein (39.8 kD). Both B1 and B3 are not glycoproteins, because neither do they interact with Shiff_reagent, nor show ultraviolet characteristics of a typical glycoprotein.
基金We thank Mary Bryk and Timothy Hall for critical suggestions to improve the manuscript,David Stelly and Keerti Rathore for assistance in GFP localization studies in onion cells,and Stanislav Vitha in the Microscopy and Imaging Center at Texas A&M University for technical support for epifluorescence microscopic image analysis in the transgenic plants.The work is supported by grants from the National Institutes of Health(GM067015)the National Science Foundation Plant Genome Research Program(DBI0077774)to Z J C.
文摘Arabidopsis thaliana histone deacetylase 1 （AtHD1 or AtHDA19）, a homolog ot yeast RPD3, is a global regulator ot many physiological and developmental processes in plants. In spite of the genetic evidence for a role of AtHD1 in plant gene regulation and development, the biochemical and cellular properties ofAtHD 1 are poorly understood. Here we report cellular localization patterns ofAtHD 1 in vivo and histone deacetylase activity in vitro. The transient and stable expression of a green fluorescent protein （GFP）-tagged AtHD1 in onion cells and in roots, seeds and leaves of the transgenic Arabidopsis, respectively, revealed that AtHD1 is localized in the nucleus presumably in the euchromatic regions and excluded from the nucleolus. The localization patterns ofAtHD 1 are different from those of AtHD2 and AtHDA6 that are involved in nucleolus formation and silencing of transgenes and repeated DNA elements, respectively. In addition, a histone deacetylase activity assay showed that the recombinant AtHD 1 produced in bacteria demonstrated a specific histone deacetylase activity in vitro. The data suggest that AtHD 1 is a nuclear protein and possesses histone deacetylase activities responsible for global transcriptional regulation important to plant growth and development.
文摘Objective： The aim of the study was to investigate the expression and clinical significance of aldehyde dehydrogenase 1 （ALDH1） in breast cancer patients. Methods： The expression of ALDH1 protein was examined by immunohistochemical staining in 96 breast cancer tissues. The disease-free survival analysis of patients was evaluated based on the clinical follow-up data. Results： Expression of ALDH1 protein had significant correlations with ER, PR, and HER2 proteins （P 〈 0.05）, but had no significant correlations with age, tumor size, clinical stage, P-glycoprotein, and lymph node status （P 〉 0.05）. The 2-year disease-free survival rate of ALDHl-positive patients was lower than that of ALDHl-negative patients （P 〈 0.05）. ALDHl-positive patients undergoing chemotherapy and hormonal therapy had lower 2-year disease-free survival rate than ALDHl-negative patients （P 〈 0.05）. Conclusion： ALDH1 expression might play an important role in drug resistant, and ALDH1 may be used as a prognostic marker.
