Abstract: In the present study，a novel C2H2-type zinc finger protein gene，PtrZPT2-2，was cloned
from trifoliate orange by in silico and RT-PCR approaches. The PtrZPT2-2 encodes a protein of 159 amino
acid residues with a predicted molecular mass of 17.28 kD and an isoelectric point of 9.51. The PtrZPT2-2
protein contains two C2H2-type zinc finger domains，and a putative transcription repression domain
（EAR/DLN-box）at the C-terminus. Phylogenetic analysis showed that the PtrZPT2-2 clustered with
PtaZFP2，ZPT2-12，ZPT2-13，ZAT12 and ZAT7. PtrZPT2-2 shared high identity with other C2H2-type
zinc finger proteins involved in abiotic stress responses. Semi-quantitative PCR analysis showed that
expression of PtrZPT2-2 was upregulated by cold，salt，drought and ABA treatments in leaves，stems and
roots of trifoliate orange seedlings. Our data suggested that PtrZPT2-2 is a new member of the C2H2-type
zinc finger protein genes and may play an important role in response to cold，salt，drought and ABA
stresses in citrus.

Key words: trifoliate orange, C2H2-type zinc finger, PtrZPT2-2