Objective     To study the secretion expression of human TALL-1 cDNA in

Pichia Pa

storis and to obtain recombinant human TALL-1 of good biological activity.      Methods     The human TALL-1 gene was cloned into yeast expression vector pPIC9K containing AOXI promoter and the sequences of secreting signal peptides. Recombinant plasmid was linearized by

Sac

Ⅰ and transformed into

Pichia Pastoris

GS115 competent cells. Positive integrated clones were screened out and cultured in flasks

and hTALL-1 was expressed under the induction of 1% methanol. Biological activities were analyzed with ELISA and MTT assay.      Results     Human TALL-1 gene was expr

essed in BMMY after optimization of inducing expression condition. The recombinant could combine with specific antibody and the expressed product could inhibit the proliferation of Hela  cells.      Conclusion     The secretion expression of human TALL-1 was successfully achieved in

Pichia Pastoris

expression system. The recombinant human TALL-1 could be used for further study on its structure and functions.