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Our world is composed of various materials with different structures, where spin structures have been playing a pivotal role in spintronic devices of the contemporary information technology. Apart from conventional collinear spin materials such as collinear ferromagnets and collinear antiferromagnetically coupled materials, noncollinear spintronic materials have emerged as hot spots of research attention due to exotic physical phenomena. In this review, we first introduce two types of noncollinear spin structures, i.e., the chiral spin structure that yields real-space Berry phases and the coplanar noncollinear spin structure that could generate momentum-space Berry phases, and then move to relevant novel physical phenomena including topological Hall effect, anomalous Hall effect, multiferroic, Weyl fermions, spin-polarized current and spin Hall effect without spin–orbit coupling in these noncollinear spin systems. Afterward, we summarize and elaborate the electric-field control of the noncollinear spin structure and related physical effects, which could enable ultralow power spintronic devices in future. In the final outlook part, we emphasize the importance and possible routes for experimentally detecting the intriguing theoretically predicted spin-polarized current, verifying the spin Hall effect in the absence of spin–orbit coupling and exploring the anisotropic magnetoresistance and domain-wall-related magnetoresistance effects for noncollinear antiferromagnetic materials. [ABSTRACT FROM AUTHOR]

Previous studies have reported that genome‐wide DNA methylation and differentially expressed genes and proteins are closely associated with drug resistance in Mycobacterium tuberculosis (M. tuberculosis). However, no reports have explored such associations in para‐aminosalicylic acid (PAS)‐resistant M. tuberculosis H37Rv. Here, we investigated genome‐wide methylation and transcriptome and proteome changes to explore the associations between specific genes and PAS resistance in M. tuberculosis H37Rv. The results revealed that 1,388 differentially methylated (1,161 hypermethylated and 227 hypomethylated) genes, 214 significantly differentially expressed (103 up‐ and 111 down‐regulated) genes and 137 differentially expressed (48 up‐ and 89 down‐regulated) proteins were regulated by PAS in M. tuberculosis H37Rv. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed that metabolic pathways and ABC transporters were closely associated with differentially methylated and expressed genes, respectively. In addition, correlation analysis revealed that differentially methylated genes were negatively correlated with their transcriptional levels in PAS‐resistant M. tuberculosis H37Rv. Furthermore, the existence of five hypermethylated candidate genes (esxC, fabG3, fbpB, papA1 and pks2) in PAS‐resistant M. tuberculosis H37Rv was verified using protein–protein interaction analysis in the STRING database. The integrated DNA methylation and transcriptome and proteome analysis could provide valuable resources for epigenetics studies in PAS‐resistant M. tuberculosis H37Rv. [ABSTRACT FROM AUTHOR]