Identification And Functional Analysis Of Secreted Effector, MeCPI, From Meloidogyne Enterolobii

Meloidogyne enterolobii has a wide host range and high reproductive performance. It also has a high pathogenicity and can even infect the tomato(Solanum lycopersicum) and pepper(Capsicum frutescens) that carry the Mi gene. So far, M. enterolobii has become one of the most important pathogens in the tropical and subtropical area.In the South China, M. enterolobiihas a wide distribution and has been extracted from more than 20 kinds of economical crop and several kinds of tropical fruit. During its parasitic process, M. enterolobii secreted numerous proteins whichnamed effector proteins to affect physiological activity of the plant cell. Identifying and analyzing the function of these effector proteins would help to clarify the pathogenic mechanism of M. enterolobii. In this paper, the effector protein of M. enterolobii, Me CPI, was studied and the main results are as follows:1. The Me CPI gene was obtained by the method of homology-based cloning. The c DNA of Me CPI is 444 bp long. And the DNA is 1543 bp long, containing 4 introns. The protein coded by Me CPI gene contains 147 amino acid residues and one cystatin conserved domain. And the signal peptide sequence was predicted by Signal P.2. The in situ hybridization suggested that Me CPI was localized in the dorsal esophageal gland of M. enterolobii.3. The result of q RT-PCR showed that the highest expression level of Me CPI appeared in the par-J4 and a high expression level was kept in the par-J3, while the expression level was quite low in both eggs and pre-J2. This suggested that Me CPI may be associated with the colonization of M. enterolobii.4. A prominent decreasednumber of the mature females was observed after the effective gene silencing of Me CPI in vitro, showing a similar conclusion to that of q RT-PCR.5. The transient expression of Me CPI gene was also studied. The proteins expressed by the complete c DNA sequence and the c DNA without signal peptide sequence were detected by Western-blot, providing referable information for further studies.