Funding for this research was provided by:
National Natural Science Foundation of China (31672366)
Received: 8 November 2019
Accepted: 3 February 2020
First Online: 18 February 2020
Ethics approval and consent to participate
: This article does not contain any studies with human participants or animals performed by any of the authors.
: All authors agree to submit this manuscript to <i>AMB Express</i> for publication.
: The authors declare that they have no competing interests.