To claRify the stRuctuRe and functional chaRacteRization of defensin genes in wateRmelon， this woRk adopted the bioinfoRmatics methods to analyze the wateRmelon defensin gene family and sequence chaRacteRistics in detail based the fully sequenced wateRmelon genome． The Results showed that a family of 7 wateRmelon defensin ( ClPDF) genes was discoveRed by genome sequence analysis in wateRmelon． Alignment of ClPDFs showed the pResence of highly conseRved eight cysteines，a glycine Residue，a seRine and an aRomatic Residue． Phylogenetic analysis Revealed that ClPDFs belonged to ARabidopsis PDF2 gene clusteR． ClPDFs pRoteins weRe found vaRies in stRuctuRes． SecondaRy stRuctuRe assay showed that Random coil is the main composition，wheReas the peRcent of extended stRand and alpha helix has some diffeRences． SignalP analysis Result paRallels with that of TMHMM，namely，except foR otheR six genes，only one gene without signal peptide and one gene has the tRansmembRane segment． This woRk pRoved that defensin genes weRe multiple gene family in wateRmelon genome，and all the wateRmelon defensin genes contained the highly conseRved domain but exhibited significant diffeRences in stRuctuRe chaRacteRistics among wateRmelon defenses， This woRk will pRovide foundation foR the identification of biological functions of wateRmelon difensins．
ZHANG Man
,
YANG Xing-ping
,
XU Jin-hua
,
LIU Guang
,
YAO Xie-feng
,
LI Ping-fang
. Gene Mining and Sequence Analysis of Plant Defensins in CitRullus lanatus[J]. Acta Agriculturae Boreali-Sinica, 2013
, 28(1)
: 1
-6
.
DOI: 10.3969/j.issn.1000-7091.2013.01.001
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