BIG3 and BIG5 Redundantly Mediate Vesicle Trafficking in Arabidopsis.
BIG3 and BIG5 Redundantly Mediate Vesicle Trafficking in Arabidopsis.
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BIG3 和 BIG5 冗余介导拟南芥中的囊泡运输
DOI：
10.3390/biom11050732
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发表时间：
2021-05-14
期刊：
影响因子：
5.5
通讯作者：
Wu W
中科院分区：
文献类型：
--
作者：
Suo Y;Hu F;Zhu H;Li D;Qi R;Huang J;Wu W
囊泡运输在真核生物不同膜系统之间传递各种各样的货物中起着重要作用。布雷菲德菌素A（Brefeldin A，BFA）抑制的鸟嘌呤核苷酸交换因子（Guanine Nucleotide Exchange Factor，GEF）（BIG）通过激活ADP-核糖基化因子（ADP-ribosylation Factor，ARF）调节高尔基体网络（trans-Golgi network，TGN）上的囊泡出芽和内体再循环。在拟南芥的5个BIGs中，BIG 5在分泌途径中介导质膜或内体上的ARF依赖性运输，而BIG 1至BIG 4（BIG 1-BIG 4）的成员在TGN上介导分泌途径。然而，越来越多的证据表明，BIG 5可以与BIG 1-BIG 4冗余地发挥作用，以调节囊泡运输，以响应各种细胞内和细胞外刺激。在这项研究中，我们的遗传分析表明，BIG 5至少与BIG 3在细胞增殖中发挥重叠作用。为了阐明BIG 5和BIG 3调节生物过程的分子机制，我们研究了BIGs对两种跨膜蛋白表达模式的影响，PINFORMED 2（PIN 2）位于根表皮细胞中，G蛋白信号转导调节因子1（RGS 1）位于质膜中。我们的数据显示，在不存在BFA的情况下，big 3 big 5中的PIN 2极性分布略有降低，并且在big 3 big 5中，通过0.1 µM BFA处理，PIN 2极性分布显著降低。进一步的分析显示，来自质膜的BFA体仅在野生型（WT）、big 3和big 5细胞中观察到，但在big 3 big 5细胞中未观察到。这些结果表明，BIG 5和BIG 3在从质膜到TGN的内体再循环途径中是功能冗余的。另一方面，单个BIG 3或BIG 5突变对RGS 1的质膜表达没有影响，而BIG 3和BIG 5中的双突变导致大量的RGS 1保留在囊泡中，表明BIG 3和BIG 5在介导蛋白质运输中起冗余作用。透射电镜观察显示big 3 big 5细胞中高尔基体的超微结构异常，与BFA处理的WT细胞相似。两者合计，我们的数据提供了几个新的证据，支持BIGs在囊泡贩运中发挥了冗余的作用，也可能在维持高尔基体结构的完整性在拟南芥。
Vesicle trafficking plays an important role in delivering a diverse range of cargoes between different membranous systems in eukaryotes. It is well documented that the brefeldin A (BFA)-inhibited guanine nucleotide exchange factor (GEF), named BIG, regulates vesicle budding at the trans-Golgi network (TGN) and recycling endosomes through activating the ADP-ribosylation factor (ARFs). Among the five BIGs in Arabidopsis, BIG5 is characterized to mediate ARF-dependent trafficking at the plasma membrane or endosomes while the members from BIG1 to BIG4 (BIG1-BIG4) at the TGN in the secretory pathway. However, evidence is increasing to suggest that BIG5 can function redundantly with BIG1-BIG4 to regulate vesicular trafficking in response to various intra- and extra-cellular stimuli. In this study, our genetic analysis showed that BIG5 played an overlapping role at least with BIG3 in cell proliferation. To elucidate molecular mechanisms underlying the BIG5- and BIG3-regulated biological processes, we examined the effect of BIGs on expression patterns of the two transmembrane proteins, PINFORMED 2 (PIN2) epically localized in root epidermal cells and the regulator of G protein signaling 1 (RGS1) localized in the plasma membrane. Our data showed that the PIN2 polar distribution was slightly reduced in big3 big5 in the absence of BFA, and it was significantly reduced by the treatment of 0.1 µM BFA in big3 big5. Further analysis revealed that BFA bodies derived from the plasma membrane were only observed in wild type (WT), big3 and big5 cells, but not in the big3 big5 cells. These results indicate that BIG5 and BIG3 are functionally redundant in the endosome recycling pathway from the plasma membrane to TGN. On the other hand, the single BIG3 or BIG5 mutation had no effect on the plasma membrane expression of RGS1, whereas the double mutations in BIG3 and BIG5 led to a significant amount of RGS1 retained in the vesicle, indicating that BIG3 and BIG5 act redundantly in mediating protein trafficking. Furthermore, transmission electron microscopy assays showed that Golgi ultrastructure in big3 big5 cells was abnormal and similar to that in BFA-treated WT cells. Taken together, our data provide several new lines of evidence supporting that BIGs play a redundant role in vesicular trafficking and probably also in maintaining the Golgi structural integrity in Arabidopsis.
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影响因子：
64.5
作者：
Geldner, N;Anders, N;Jürgens, G
通讯作者：
Jürgens, G
影响因子：
21.3
作者：
Richter, Sandra;Mueller, Lena M.;Juergens, Gerd
通讯作者：
Juergens, Gerd
DOI：
10.1007/978-1-4939-3804-9_1
发表时间：
2016-01-01
期刊：
UNCONVENTIONAL PROTEIN SECRETION
影响因子：
--
作者：
Viotti, Corrado
通讯作者：
Viotti, Corrado
影响因子：
5.6
作者：
Xue, Shan;Zou, Junjie;Le, Jie
通讯作者：
Le, Jie
DOI：
10.1038/nrm3117
发表时间：
2011-06
期刊：
Nature reviews. Molecular cell biology
影响因子：
--
作者：
通讯作者：
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