Author contributions
C.G.Y., X.M.Z. and W.Z.J. designed the research, analyzed data and revised the manuscript. C.L.Y., J.L. and Y.Y.H. performed experiments, analyzed data and wrote the manuscript. Q.S.G. and Z.Y.P. collected samples, performed experiments and analyzed data. S.L.Y. and X.R. analyzed data. L.C. revised the manuscript and R.C.Y, M.D., H.L.Z., H.Q.Z., X.X.J. and X.N.W. collected samples.