Chlorophyllase is transcriptionally regulated by CsMYB308/CsDOF3 in young leaves of tea plant

Chlorophyll contributes to tea coloration, which is an important factor in tea quality. Chlorophyll metabolism is induced by light, but the transcriptional regulation responsible for light-induced chlorophyll metabolism is largely unknown in tea leaves. Here, we characterized a chlorophyllase1 gene CsCLH1 from young tea leaves and showed it is essential for chlorophyll metabolism, using transient overexpression and silencing in tea leaves and ectopic overexpression in Arabidopsis. CsCLH1 was significantly induced by high light. The DOF protein CsDOF3, an upstream direct regulator of CsCLH1, was also identified. Acting as a nuclear-localized transcriptional factor, CsDOF3 responded for light and repressed CsCLH1 transcription and increased chlorophyll content by directly binding to the AAAG cis-element in the CsCLH1 promoter. CsDOF3was able to physically interact with the R2R3-MYB transcription factor CsMYB308 and interfere with transcriptional activity of CsCLH1. In addition, CsMYB308 binds to the CsCLH1 promoter to enhance CsCLH1 expression and decrease chlorophyll content. CsMYB308 and CsDOF3 act as an antagonistic complex to regulate CsCLH1 transcription and chlorophyll in young leaves. Collectively, the study adds to the understanding of the transcriptional regulation of chlorophyll in tea leaves in response to light and provides a basis for improving the appearance of tea.

ONE-PARAMETER FINITE DIFFERENCE METHODS AND THEIR ACCELERATED SCHEMES FOR SPACE-FRACTIONAL SINE-GORDON EQUATIONS WITH DISTRIBUTED DELAY

This paper deals with numerical methods for solving one-dimensional(1D)and twodimensional(2D)initial-boundary value problems(IBVPs)of space-fractional sine-Gordon equations(SGEs)with distributed delay.For 1D problems,we construct a kind of oneparameter finite difference(OPFD)method.It is shown that,under a suitable condition,the proposed method is convergent with second order accuracy both in time and space.In implementation,the preconditioned conjugate gradient(PCG)method with the Strang circulant preconditioner is carried out to improve the computational efficiency of the OPFD method.For 2D problems,we develop another kind of OPFD method.For such a method,two classes of accelerated schemes are suggested,one is alternative direction implicit(ADI)scheme and the other is ADI-PCG scheme.In particular,we prove that ADI scheme can arrive at second-order accuracy in time and space.With some numerical experiments,the computational effectiveness and accuracy of the methods are further verified.Moreover,for the suggested methods,a numerical comparison in computational efficiency is presented.

Weighted stationary phase of higher orders

The subject matter of this paper is an integral with exponential oscillation of phase f（x） weighted by g（x） on a finite interval [α, β]. When the phase f（x） has a single stationary point in （α,β）, an nth-order asymptotic expansion of this integral is proved for n ≥ 2. This asymptotic expansion sharpens the classical result for n = 1 by M. N. Huxley. A similar asymptotic expansion was proved by V. Blomer, R. Khan and M. Young under the assumptions that f（x） and g（x） are smooth and g（x） is compactly supported on R. In the present paper, however, these functions are only assumed to be continuously differentiable on [α,β] 2n ＋ 3 and 2n ＋ 1 times, respectively. Because there are no requirements on the vanishing of g（x） and its derivatives at the endpoints α and β, the present asymptotic expansion contains explicit boundary terms in the main and error terms. The asymptotic expansion in this paper is thus applicable to a wider class of problems in analysis, analytic number theory, and other fields.

Double square moments and subconvexity bounds for Rankin-Selberg L-functions of holomorphic cusp forms

Let f and g be holomorphic cusp forms of weights k1 and k2 for the congruence subgroups TO(N1)and Γ0(N2),respectively.In this paper the square moment of the Rankin-Selberg L-function for f and g in the aspect of both weights in short intervals is bounded,when k1^ε <<k^2<<k1^1-ε.These bounds are the mean Lindelof hypothesis in one case and subconvexity bounds on average in other cases.These square moment estimates also imply subconvexity bounds for individual L(1/2+it,f×g) for all g when f is chosen outside a small exceptional set.In the best case scenario the subconvexity bound obtained reaches the Weyl-type bound proved by Lau et al.(2006) in both the k1 and k2 aspects.

Moments of L-Functions Attached to the Twist of Modular Form by Dirichlet Characters

Let f（z） be a holomorphic cusp form of weight κ with respect to the full modular group SL2（Z）. Let L（s, f） be the automorphic L-function associated with f（z） and χ be a Dirichlet character modulo q. In this paper, the authors prove that unconditionally for k =1/n with n ∈ N,Mk（q,f）=∑χ（mod q）χ≠χ0｜L（1/2,f χ）｜^2k〈〈 kФ（q）（log q）^k^2, and the result also holds for any real number 0 〈 k 〈 1 under the GRH for L（s, f χ）.The authors also prove that under the GRH for L（s, f χ）,for any real number k 〉 0 and any large prime q.