Cloning And Transformation Of Sl-XRN2 And Sl-XRN4 Gene In Tomato

5'-3'exoribonuclease, an important enzyme which exists in virous organisms, plays significant roles during the process of growth and development. XRN family is a 5'-3'exoribonuclease family which exists widely in animals, plants and microorgamisms. XRN family includes, as far as been known, Xrn1p, Xrn2p, XRN2, XRN3 and XRN4 with different functions and locations in cell. XRN2 locates in the nucleus and functions in the processing of pre-rRNA and degradation of MIRNA-loop and aberrant RNAs while XRN4 functions in the degradation of miRNA-cleavage product and aberrant RNAs and ethylene signaling pathway in the cytoplasm.Most researches of XRN family in plants were made in Arabisopsis, a few were also in tobaccos. Although Arabidopsis is an important model plant for biological research, it is restricted by some aspects, especially the unremarkable trait of the development of the fruit. Tomato, an important model in fruit research, has remarkable traits during the fruit developmental process. Therefore, using tomato as model can reveal the function of XRN family during the plant development especially fruit ripening and senescence, which provide great value to the mechanism of fruit ripening and senescence.In order to reveal the function of XRN2 and XRN4 in plants, we cloned and identified the XRN2 and XRN4 gene in tomato and did research on bioinfomatics and genetic transformation. The main results include:①Sl-XRN2 gene was amplified by RT-PCR. Sequencing results showed that the ORF is 3 327 bp which encodes 1 109 amino acids.②Sl-XRN4 gene was amplified by RT-PCR. Sequencing results showed that the ORF is 2 937 bp which encodes 978 amino acids.③Expression analysis result of Sl-XRN2 by Semiquantitative-PCR showed that Sl-XRN2 expressed highest in roots.④Sl-XRN2 can be up-regulated by wound stress.⑤Sense and antisense insertion of Sl-XRN2 was constructed into vectors and transformed into Agrobacterium GV3101 after being identified by PCR and sequencing.⑥Sense and antisense insertion of Sl-XRN4 was constructed into vectors and transformed into Agrobacterium GV3101 after identified by PCR and sequencing.⑦Agrobacterium-mediate transformation of vectors was made in tomato and being screened from Hyg 100mg/L pressure.