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Cheng M, Iyer AK, Zhou X, Tyner A, Liu Y, Shehzad MA, Goswami P, Chung DY, Kanatzidis MG, Dravid VP. Tuning the Structural and Magnetic Properties in Mixed Cation Mn xCo 2-xP 2S 6. Inorg Chem 2022; 61:13719-13727. [PMID: 35998562 DOI: 10.1021/acs.inorgchem.2c01116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The metal thiophosphates (MTP), M2P2S6, are a versatile class of van der Waals materials, which are notable for the possibility of tuning their magnetic properties with the incorporation of different transition-metal cations. Further, they also offer opportunities to probe the independent and synergistic role of the magnetically active cation sublattice when coupled to P2Q6 polyhedra. Herein, we report the structural, magnetic, and electronic properties of the series of MTPs, MnxCo2-xP2S6 (x = 0.25, 0.5, 1, 1.5, 1.75) synthesized by the P2S5 flux method. Structural and elemental analysis indicates a homogeneous stoichiometry in the MnxCo2-xP2S6 compounds. We observe that a correlation is apparent between the intensities of specific Raman modes and Raman shifts with respect to the alloying ratio between Mn and Co. Magnetic susceptibility measurements indicate that the alloyed systems adopt an ordered antiferromagnetic (AFM) configuration with a dependence of the Néel temperature on the alloying ratio. A possible magnetic frustration behavior was observed for the composition MnCoP2S6 due to magnetic moment compensation as the alloying ratio between Mn and Co approaches parity. Interestingly, mixed oxidation states of the metal cation species are also observed in MnxCo2-xP2S6 along with a linear dependence of the work function on the alloying ratio of Mn and Co.
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Affiliation(s)
- Matthew Cheng
- Department of Material Science and Engineering, Northwestern University, Evanston, Illinois 60208, United States
| | - Abishek K Iyer
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | - Xiuquan Zhou
- Materials Science Division, Argonne National Laboratory, 9700 South Cass Avenue, Lemont, Illinois 60439, United States
| | - Alexander Tyner
- Graduate program in Applied Physics, Northwestern University, Evanston, Illinois 60208, United States
| | - Yukun Liu
- Department of Material Science and Engineering, Northwestern University, Evanston, Illinois 60208, United States
| | - M Arslan Shehzad
- Department of Material Science and Engineering, Northwestern University, Evanston, Illinois 60208, United States.,Northwestern University Atomic and Nanoscale Characterization Experimental (NUANCE) Center, Northwestern University, Evanston, Illinois 60208, United States
| | - Pallab Goswami
- Graduate program in Applied Physics, Northwestern University, Evanston, Illinois 60208, United States.,Department of Physics and Astronomy, Northwestern University, Evanston, Illinois 60208, United States
| | - Duck Young Chung
- Materials Science Division, Argonne National Laboratory, 9700 South Cass Avenue, Lemont, Illinois 60439, United States
| | - Mercouri G Kanatzidis
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | - Vinayak P Dravid
- Department of Material Science and Engineering, Northwestern University, Evanston, Illinois 60208, United States.,Northwestern University Atomic and Nanoscale Characterization Experimental (NUANCE) Center, Northwestern University, Evanston, Illinois 60208, United States.,International Institute for Nanotechnology (IIN), Northwestern University, Evanston, Illinois 60208, United States
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Abstract
The FoxM1 transcription factor plays critical roles in the expression of genes that are essential for cell proliferation. FoxM1 null or depleted cells fail to progress through mitosis, as expression of several mitotic genes depends upon FoxM1. The transcriptional activity of FoxM1 is stimulated by cyclin-cdk-mediated phosphorylation at a site within the transcriptional activation domain. Here, we characterize the role of an N-terminal inhibitory domain in the transcriptional activity of FoxM1. Deletion of the N-terminal 232 amino-acid residues increases the transcriptional and transforming activities of FoxM1. Moreover, while the activity of the full-length FoxM1 is stimulated by growth factors, the activity of the N-terminal deletion mutant is constitutively high in all phases of the cell cycle. The N-terminal deletion also eliminates the requirement for cyclin-cdk to activate FoxM1. We provide evidence that the N-terminal domain interacts with the C-terminal half of the transcription factor to attenuate its transcriptional activity. Moreover, the N-terminal fragment inhibits the transcriptional activity of FoxM1 in G1/S cells, but not in G2/M cells. Our results suggest that cyclin-cdk phosphorylates FoxM1 to counteract the inhibition by the N-terminal domain to fully activate FoxM1 in G2/M phase.
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Affiliation(s)
- H J Park
- Department of Biochemistry and Molecular Genetics (M/C 669), College of Medicine, University of Illinois, Chicago, IL 60607, USA
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Vassar R, Rosenberg M, Ross S, Tyner A, Fuchs E. Tissue-specific and differentiation-specific expression of a human K14 keratin gene in transgenic mice. Proc Natl Acad Sci U S A 1989; 86:1563-7. [PMID: 2466292 PMCID: PMC286738 DOI: 10.1073/pnas.86.5.1563] [Citation(s) in RCA: 289] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
A construct containing approximately 2500 base pairs (bp) of 5' upstream and approximately 700 bp of 3' downstream sequence was used to drive the expression of an intronless human K14 gene in vitro and in vivo. To track the expression of the gene, a small sequence encoding the antigenic portion of neuropeptide substance P was inserted in frame 5' to the TGA translation stop codon of the gene. Surprisingly, this gene was expressed promiscuously in a wide variety of cultured cells transiently transfected with the construct. In contrast, when introduced into the germ line of transgenic mice, the construct was expressed in a fashion analogous to the endogenous K14 gene--namely, in the basal layer of stratified squamous epithelia. Our results suggest that some regulatory mechanism is overridden as a consequence of transient transfection but that sequences that can control proper K14 expression are present in the construct. The appropriate tissue-specific and differentiation-specific expression of K14.P in transgenic mice is an important first step in characterizing a promoter that could be employed to drive the foreign expression of drug-related genes in the epidermis of skin grafts.
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Affiliation(s)
- R Vassar
- Department of Molecular Genetics and Cell Biology, University of Chicago, IL 60637
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