http://www.abbs.info E-mail: [email protected]
ISSN 0582-9879 Acta Biochimica et Biophysica Sinica 2004, 36(7): 467–476 CN 31-1300/Q
Isolation and Partial Characterization of a Novel Pollen-specific
cDNA with Multiple Polyadenylation Sites from Wheat
Yong-Feng JIN* and Teng-Fei BIAN
Institute of Biochemistry, Zhejiang University, Hangzhou 310029,
China
Abstract A novel pollen-specific full-length cDNA clone PSG076 was
isolated using suppression subtractive hybridization and 5'/3'
RACE techniques. PSG076 was shown to exhibit multi-site polyadenylation
by sequencing the 3' ends of the cDNAs. At least six transcripts with
different length were produced from the single gene based on different poly(A)
tail attachment sites. However, polyadenylation consensus sequence AAUAAA was
not seen at the 3'-untranslated sequence. PSG076 contained a 299
bp 5' untranslated region and an open reading frame of 663 bp encoding a
221 amino acid peptide with pI of 4.31. A blast search revealed that this
sequence did not show a significant similarity to any genes deposited in the
public database. Southern blot indicated that PSG076 was a single copy
gene. Northern blot and RT-PCR analysis indicated that PSG076
transcripts showed specific expression in mature pollen, and weak or
undetectable signals in uninucleate microspore, immature seed, stem, young
leave, root and ovary. Further analysis of the expression pattern in
gametophyte showed that PSG076 transcripts were undetectable in
uninucleate, binucleate microspore and pollen at early stage, and were first
detectable and increased rapidly at middle and late stages of pollen
development with the maximum level in mature pollen and also expressed in
germinating pollen in vivo, suggesting that PSG076 might play a role in pollen germination and pollen tube growth in addition to its function in maturation. The evidences gathered in
this work indicated that the six different transcripts from the single gene
were differentially expressed during pollen development.
Key words wheat (Triticum aestivum L.); pollen-specific cDNA;
suppression subtractive hybridization; multiple-site polyadenylation;
differential expression
-----------------
Received: April 15, 2004 Accepted: May 25, 2004
This work is supported by a grant from the National Natural Science
Foundation of China (No. 30370759)
*Corresponding author: Tel, 86-571-86971414; Fax, 86-571-86971501;
E-mail, [email protected]