730 Plant Mol Biol Rep(2011)29:723-732 Nsterile line Omaintainer line a 1.2 3 Salt stress b Cold stress 2.5 0.8 0.6 1.5 1 0.2 0.5 0 0 0.5 0.8 0.4 0.6 03 0.2 04 0.1 0.2 10 0 10 Time (Hour) Time (Hour) 2.5 Heat stress 1.5 1 0.5 囹图 1.5 0 2 6 10 Time (Hour) Fig.5 Quantitative analysis of BcHSP8/-4 mRNA in different tissues maintainer and sterility lines after heat shock treatment analyzed by of maintainer and sterility lines by real-time RT-PCR.a BcHSP81-4 real-time RT-PCR.The x-axis 0,before stress treatments 2-10-2,4, relative expression in maintainer and sterility lines after salt stress 6,8,and 10 h during stress treatments (salt stress at 0.1 M NaCl;heat treatment analyzed by real-time RT-PCR.b BcHSP8/-4 relative shock at 35C;cold stress at 4C).The y-axis:relative expression of expression in maintainer and sterility lines after cold stress treatment BcHSP81-4 mRNA in different stress treatments.Each data point analyzed by real-time RT-PCR.c BcHSP81-4 relative expression in represents mean SE (n=3) development.It implied the important role of BcHSP81-4 in is almost unchanged,low level in normal flower develop- the male sterile of pol CMS in non-heading Chinese ment (Fig.4).It is highly upregulated,however,in the stage cabbage. of pre-bud formation in pol CMS (Fig.4).That also implies HSP is the center of many cellular processes including some relationship between the HSP expression and the growth,cell cycling,apoptosis,development,and evolution male sterility. (Jackson et al.2004).Most research about fertility and HSP Actually,different HSPs is responsive to different stress. showed that Hsp is essential for the normal development of The central component of the heat shock response is flower,such as bobl (small heat shock protein)mutant in oxidative stress (Haralampidis et al.2002).The mtDNA Arabidopsis exhibit reduced fertility (Perez et al.2008),and of pol cytoplasm was distinguished from the mtDNAs by many Hsps are expressed in microspores or mature pollen restriction analysis (Erickson et al.1986).Analysis of (Magnard et al.1996;Haralampidis et al.2002).HSP cybrid lines has indicated that the determinants for pol proteins play a role in protecting cell proteins at various CMS reside in the mitochondrial genome (Kemble and developmental stages (Mery et al.2008).But some also Barsby 1988).The imbalance of mitochondrial energy showed that the expression of HSP is higher in sterile line metabolism is the cause of male sterility.That cause the than that of fertile line (Sheoran et al.2009).and the oxidative stress,which was proved by the higher activities expression of Cihsp70 even is required for the switch from of POD,SOD,and CAT in CMS line than those in its self-fertility to self-sterility in Ciona intestinalis (Marino et maintainer line (Deng et al.2007).Maybe it is that al.1998).Here,in our paper,the expression of BcHSP81-4 BcHSP81-4 is responsive to the oxidative stress in ≌Springerdevelopment. It implied the important role of BcHSP81-4 in the male sterile of pol CMS in non-heading Chinese cabbage. HSP is the center of many cellular processes including growth, cell cycling, apoptosis, development, and evolution (Jackson et al. 2004). Most research about fertility and HSP showed that Hsp is essential for the normal development of flower, such as bob1 (small heat shock protein) mutant in Arabidopsis exhibit reduced fertility (Perez et al. 2008), and many Hsps are expressed in microspores or mature pollen (Magnard et al. 1996; Haralampidis et al. 2002). HSP proteins play a role in protecting cell proteins at various developmental stages (Mery et al. 2008). But some also showed that the expression of HSP is higher in sterile line than that of fertile line (Sheoran et al. 2009), and the expression of Cihsp70 even is required for the switch from self-fertility to self-sterility in Ciona intestinalis (Marino et al. 1998). Here, in our paper, the expression of BcHSP81-4 is almost unchanged, low level in normal flower develop￾ment (Fig. 4). It is highly upregulated, however, in the stage of pre-bud formation in pol CMS (Fig. 4). That also implies some relationship between the HSP expression and the male sterility. Actually, different HSPs is responsive to different stress. The central component of the heat shock response is oxidative stress (Haralampidis et al. 2002). The mtDNA of pol cytoplasm was distinguished from the mtDNAs by restriction analysis (Erickson et al. 1986). Analysis of cybrid lines has indicated that the determinants for pol CMS reside in the mitochondrial genome (Kemble and Barsby 1988). The imbalance of mitochondrial energy metabolism is the cause of male sterility. That cause the oxidative stress, which was proved by the higher activities of POD, SOD, and CAT in CMS line than those in its maintainer line (Deng et al. 2007). Maybe it is that BcHSP81-4 is responsive to the oxidative stress in Fig. 5 Quantitative analysis of BcHSP81-4 mRNA in different tissues of maintainer and sterility lines by real-time RT-PCR. a BcHSP81-4 relative expression in maintainer and sterility lines after salt stress treatment analyzed by real-time RT-PCR. b BcHSP81-4 relative expression in maintainer and sterility lines after cold stress treatment analyzed by real-time RT-PCR. c BcHSP81-4 relative expression in maintainer and sterility lines after heat shock treatment analyzed by real-time RT-PCR. The x-axis 0, before stress treatments 2–10—2, 4, 6, 8, and 10 h during stress treatments (salt stress at 0.1 M NaCl; heat shock at 35°C; cold stress at 4°C). The y-axis: relative expression of BcHSP81-4 mRNA in different stress treatments. Each data point represents mean ± SE (n=3) 730 Plant Mol Biol Rep (2011) 29:723–732