Sulfur is essential for plant growth and development, and the molecular systems for maintaining sulfur and thiol metabolism are tightly controlled. From a biochemical perspective, the regulation of plant thiol metabol...Sulfur is essential for plant growth and development, and the molecular systems for maintaining sulfur and thiol metabolism are tightly controlled. From a biochemical perspective, the regulation of plant thiol metabolism high- lights nature＇s ability to engineer pathways that respond to multiple inputs and cellular demands under a range of con- ditions. In this review, we focus on the regulatory mechanisms that form the molecular basis of biochemical sulfur sensing in plants by translating the intracellular concentration of sulfur-containing compounds into control of key metabolic steps. These mechanisms range from the simple （substrate availability, thermodynamic properties of reactions, feedback inhi- bition, and organelle localization） to the elaborate （formation of multienzyme complexes and thiol-based redox switches）. Ultimately, the dynamic interplay of these regulatory systems is critical for sensing and maintaining sulfur assimilation and thiol metabolism in plants.展开更多
AIM: To identify the novel mutation alleles in the CYP1B1 gene of primary congenital glaucoma(PCG) patients at Shandong Province of China, and investigate their correlation with glaucomatous features.METHODS: The DNA ...AIM: To identify the novel mutation alleles in the CYP1B1 gene of primary congenital glaucoma(PCG) patients at Shandong Province of China, and investigate their correlation with glaucomatous features.METHODS: The DNA from the peripheral blood of 13 congenital glaucoma patients and 50 ethnically matched healthy controls from the affiliated hospital of Qingdao University were extracted. The coding region of the CYP1B1 gene was amplified by PCR and direct DNA sequencing was performed. Disease causing-variants were analyzed by comparing the sequences and the structures of wild type and mutant CYP1B1 proteins by PyMOL software.RESULTS: Two missense mutations, including A330 F caused by c.988 G>T&c.989 C>T, and R390H caused by c.1169 G>A, were identified in one of the 13 PCG patients analyzed in our study. A330F mutation was observed to be novel in the Chinese Han population, which dramatically altered the protein structure of CYP1B1 gene, including the changes in the ligand-binding pocket. Furthermore, R390H mutation caused the changes in heme-protein binding site of this gene. In addition, the clinical phenotype displayed by PCG patient with these mutations was more pronounced than other PCG patients without these mutations. Multiple surgeries and combined drug treatment were not effective in reducing the elevated intraocular pressure in this patient.CONCLUSION: A novel A330F mutation is identified in the CYP1B1 gene of Chinese PCG patient. Moreover, in combination with other mutation R390H, this PCG patient shows significant difference in the CYP1B1 protein structure, which may specifically contribute to severe glaucomatous phenotype.展开更多
基金This work was funded by grants from the US Department of Agriculture （NRI-2005-02518） and the National Science Foundation （MCB-0824492）. No conflict of interest declared.
文摘Sulfur is essential for plant growth and development, and the molecular systems for maintaining sulfur and thiol metabolism are tightly controlled. From a biochemical perspective, the regulation of plant thiol metabolism high- lights nature＇s ability to engineer pathways that respond to multiple inputs and cellular demands under a range of con- ditions. In this review, we focus on the regulatory mechanisms that form the molecular basis of biochemical sulfur sensing in plants by translating the intracellular concentration of sulfur-containing compounds into control of key metabolic steps. These mechanisms range from the simple （substrate availability, thermodynamic properties of reactions, feedback inhi- bition, and organelle localization） to the elaborate （formation of multienzyme complexes and thiol-based redox switches）. Ultimately, the dynamic interplay of these regulatory systems is critical for sensing and maintaining sulfur assimilation and thiol metabolism in plants.
基金Supported by “Clinical medical+X” Project from Department of Medicine of Qingdao University
文摘AIM: To identify the novel mutation alleles in the CYP1B1 gene of primary congenital glaucoma(PCG) patients at Shandong Province of China, and investigate their correlation with glaucomatous features.METHODS: The DNA from the peripheral blood of 13 congenital glaucoma patients and 50 ethnically matched healthy controls from the affiliated hospital of Qingdao University were extracted. The coding region of the CYP1B1 gene was amplified by PCR and direct DNA sequencing was performed. Disease causing-variants were analyzed by comparing the sequences and the structures of wild type and mutant CYP1B1 proteins by PyMOL software.RESULTS: Two missense mutations, including A330 F caused by c.988 G>T&c.989 C>T, and R390H caused by c.1169 G>A, were identified in one of the 13 PCG patients analyzed in our study. A330F mutation was observed to be novel in the Chinese Han population, which dramatically altered the protein structure of CYP1B1 gene, including the changes in the ligand-binding pocket. Furthermore, R390H mutation caused the changes in heme-protein binding site of this gene. In addition, the clinical phenotype displayed by PCG patient with these mutations was more pronounced than other PCG patients without these mutations. Multiple surgeries and combined drug treatment were not effective in reducing the elevated intraocular pressure in this patient.CONCLUSION: A novel A330F mutation is identified in the CYP1B1 gene of Chinese PCG patient. Moreover, in combination with other mutation R390H, this PCG patient shows significant difference in the CYP1B1 protein structure, which may specifically contribute to severe glaucomatous phenotype.
