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Robustness in biology is the stability of phenotype under diverse genetic and/or environmental perturbations. The circadian clock has remarkable stability of period and phase that-unlike other biological oscillators-is maintained over a wide range of conditions. Here, we show that the high fidelity of the circadian system stems from robust degradation of the clock protein PERIOD. We show that PERIOD degradation is regulated by a balance between ubiquitination and deubiquitination, and that disruption of this balance can destabilize the clock. In mice with a loss-of-function mutation of the E3 ligase gene β-Trcp2, the balance of PERIOD degradation is perturbed and the clock becomes dramatically unstable, presenting a unique behavioral phenotype unlike other circadian mutant animal models. We believe that our data provide a molecular explanation for how circadian phases, such as wake-sleep onset times, can become unstable in humans, and we present a unique mouse model to study human circadian disorders with unstable circadian rhythm phases., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

In order to explore the environmental pest management method of Dorysthenes hydropicus, three strains of entomopathogenic nematodes, viz. Heterorhabditis bacteriphora (H06), Steinernema scapterisci (SS), S. carpocapsae (All) were used on larvae of Dorysthenes hydropicus, with treatments of 0, 5 000 and 10 000 nematodes each larva. The result showed that these three strains viz. All, H06 and SS had high lethal effects on the larvae. Lethal rates had dose-effects relationship with inoculation amounts. High dose treatments resulted in high mortalities and led to quick death, especially in the treatment of H06. Treatment of H06 with 10 000 nematodes per larva resulted in 100% mortality after inoculated 4 days. Different strains of these nematodes had various lethal characters, H06 with only one peak mortality, the larvae died quickly after inoculated, while All and SS with 2 peak mortalities, there was a stable stage with low mortality between the 2 peak mortalities. Entomopathogenic nematodes could be used as a hopeful method for controlling of Dorysthenes hydropicus in fields.

The mammalian molecular circadian clock in the suprachiasmatic nuclei (SCN) regulates locomotor activity rhythms as well as clocks in peripheral tissues (Reppert and Weaver, 2002; Ko and Takahashi, 2006). Constant light (LL) can induce behavioral and physiological arrhythmicity by desynchronizing clock cells in the SCN (Ohta et al., 2005). We examined how the disordered clock cells resynchronize by probing the molecular clock and measuring behavior in mice transferred from LL to constant darkness (DD). The circadian locomotor activity rhythms disrupted in LL become robustly rhythmic again from the beginning of DD, and the starting phase of the rhythm in DD is specific, not random, suggesting that the desynchronized clock cells are quickly reset in an unconventional manner by the L/D transition. By measuring mPERIOD protein rhythms, we showed that the SCN and peripheral tissue clocks quickly become rhythmic again in phase with the behavioral rhythms. We propose that this resetting mechanism may be different from conventional phase shifting, which involves light induction of Period genes (Albrecht et al., 1997; Shearman et al., 1997; Shigeyoshi et al., 1997). Using our functional insights, we could shift the circadian phase of locomotor activity rhythms by 12 h using a 15 h LL treatment: essentially producing phase reversal by a single light pulse, a feat that has not been reported previously in wild-type mice and that has potential clinical utility.

The Dof (DNA binding with one finger) proteins are plant specific transcription factors. Dof proteins are apparently encoded by a multiple gene family in higher plants. However, only one Dof gene, WPBF, was reported in wheat. In this study, a member of Dof gene family, TaDof1, was cloned from wheat. TaDof1 encode 291 amino acids, with a predicted molecular mass of 30.348 kDa. At its N-terminal end, a 52 amino acid stretch typical of Dof domain and two serine-rich stretches were observed. Sequence alignment indicated that, in Dof domain, TaDof1 share more than 75% identity with other Dof proteins of different species. TaDof1 was expressed highly in leaves and sheaths, but lowly in roots, and constitutively expressed in developing seeds of 2-12 DAP. It was interesting to note that TaDof1 was differentially expressed between hybrids F1 and parents in root, sheath and leaf. The implication of the differential expression patterns of TaDof1 was discussed in related to the up-regulation of C4 pathway related gene in hybrid rice and heterosis.