[Ca2+]cyt-ASSOCIATED PROTEIN KINASE 1 and NIMA-RELATED KINASE 2 interact during root hair cell morphogenesis.

Root hair growth has been studied to understand the principles underlying the regulation of directional growth. Arabidopsis (Arabidopsis thaliana) [Ca2+]cyt-ASSOCIATED PROTEIN KINASE 1 (CAP1) maintains normal vesicle trafficking and cytoskeleton arrangement during root hair growth in response to ammonium signaling. In the current study, we identified CAP1 SUPPRESSOR 1 (CAPS1) as a genetic suppressor of the cap1-1 mutation. The CAPS1 mutation largely rescued the short root hair phenotype of cap1-1. Loss of CAPS1 function resulted in significantly longer root hairs in cap1-1. MutMap analysis revealed that CAPS1 is identical to NIMA (NEVER IN MITOSIS A)-RELATED KINASE 2 (NEK2). In addition, our studies showed that NEK2 is expressed in root and root hairs. Its distribution was associated with the pattern of microtubule arrangement and partially co-localized with CAP1. Further biochemical studies revealed that CAP1 physically interacts with NEK2 and may enhance its phosphorylation. Our study suggests that NEK2 acts as a potential phosphorylation target of CAP1 in maintaining the stability of root hair microtubules to regulate root hair elongation.

White LED light source radar system for multi-wavelength remote sensing measurement of atmospheric aerosols.

A Mie scattering radar system with a white light-emitting diode (LED) light source is proposed for the multi-wavelength detection of atmospheric aerosols. By splitting the continuous spectrum, the multi-wavelength echo signals are extracted to achieve multi-wavelength real-time detection of atmospheric aerosols. The white LED spectrum characteristics are analyzed, and four detection wavelengths are set at 450, 525, 600, and 661 nm. The composition and detection principles of a white LED light source radar system are expounded, the design of each system part is described in detail, and the system parameters and data inversion algorithm are presented. We built a white LED light source radar system and conducted preliminary observation experiments. The results show that radar can achieve multi-wavelength real-time detection of atmospheric aerosols within a 300 m height, which can provide effective data for further study of aerosol particle distribution and lay a foundation for further studies of aerosol characteristics at special wavelengths.