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Cryptochrome 1 (CRY1) functions as a light‐responsive photoreceptor, which is crucial for circadian rhythms. The identity and function of CRY1 in Plutella xylostella remain unknown. In this study, cry1 was cloned and identified in P. xylostella. Then, a cry1‐knockout strain (Cry1‐KO) of P. xylostella with a 2‐bp deletion was established from the strain Geneva 88 (G88) using the CRISPR/Cas9 technology. No daily temporal oscillation of cry1 was observed in G88 and Cry1‐KO, and cry1 mean daily transcription of Cry1‐KO was lower than that of G88. Both G88 and Cry1‐KO demonstrated rhythmic locomotion under the light/dark condition with Cry1‐KO being more active than G88 in the daytime, whereas Cry1‐KO completely lost rhythmicity under constant darkness. The developmental period of pre‐adult of Cry1‐KO was longer than that of G88; the lifespan of the Cry1‐KO male adult was shorter than that of G88; the fecundity of Cry1‐KO was lower than that of G88; and Cry1‐KO showed lower intrinsic rate of increase (r), net reproduction rate (R0), finite increase rate (λ), and longer mean generation time (T) than G88. Our results indicate that cry1 is involved in the regulation of locomotor circadian rhythm and development in P. xylostella, providing a potential target gene for controlling the pest and a basis for further investigation on circadian rhythms in lepidopterans. [ABSTRACT FROM AUTHOR]

Collagen triple helix repeat containing 1 (Cthrc1) is a secreted protein that has been observed to lead to poorer prognosis by inducing the invasion and metastasis in different tumors; however, it has not been demonstrated that Cthrc1 is involved in tumor angiogenesis. Immunohistochemical staining of Cthrc1 and CD31 in gastrointestinal stromal tumor tissue demonstrated that Cthrc1 is associated with microvascular density. Overexpression of Cthrc1 protein may alter the properties of human umbilical vein endothelial cells (HUVECs), including migration, invasion, tubule formation and aortic ring sprouting. Small interfering RNA-mediated knockdown of Cthrc1 was performed to verify the opposite effects. Migration and tubule formation induced by Cthrc1 overexpression in HUVECs was attenuated by inhibition of phosphorylation in extracellular-signal-regulated protein kinase (ERK) and c-Jun N-terminal kinase (JNK) signaling pathways. The pro-angiogenic effect of Cthcr1 is associated with increased phosphorylation of ERK and JNK in HUVECs. Silencing the expression of Cthrc1 protein may be a promising strategy to inhibit tumor angiogenesis.

Resonate frequency and cell constant of photoacoustic spectrum system are usually calibrated by using standard gas in laboratory, whereas the resonate frequency and cell constant will be changed in-situ, leading to measurement accuracy errors, caused by uncertainties of standard gas, differences between standard and measured gas components and changes in environmental condition, such as temperature and humidity. As to overcome the above problems, we have proposed an on-line atmospheric oxygen-based calibration technology for photoacoustic spectrum system and used in measurement of concentration of carbon dioxide in atmosphere. As the concentration of atmospheric oxygen is kept as constant as 20.96%, the on-line calibration for the photoacoustic spectrum system can be realized by detecting the swept-frequency and peak signal at 763.73 nm. The cell of the PAS has a cavity with length of 100 mm and an inner diameter of 6 mm, and worked in a first longitudinal resonant mode. The influence of environmental temperature and humidity, gas components on the photoacoustic cell's performance has been theoretically analyzed, and meanwhile the resonant frequencies and cell constants were calibrated and acquired respectively using standard gas, indoor air and outdoor air. Compared with calibrated gas analyzer, concentration of carbon dioxide is more accurate by using the resonant frequency and cell constant calculated by oxygen in tested air, of which the relative error is less than 1%, much smaller than that calculated by the standard gas in laboratory. The innovation of this paper is that using atmospheric oxygen as photoacoustic spectrum system's calibration gas effectively reduces the error caused by using standard gas and environmental condition changes, and thus improves the on-line measuring accuracy and reliability of the photoacoustic spectrum system.