The conserved cysteine-rich domain of a tesmin/TSO1-like protein binds zinc in vitro and TSO1 is required for both male and female fertility in Arabidopsis thaliana.

Development of reproductive tissue and control of cell division are common challenges to all sexually reproducing eukaryotes. The Arabidopsis thaliana TSO1 gene is involved in both these processes. Mild tso1 mutant alleles influence only ovule development, whereas strong alleles have an effect on all floral tissues and cause cell division defects.