WHIRLY1 is a major organizer of chloroplast nucleoids.
WHIRLY1 is a major organizer of chloroplast nucleoids.
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DOI：
10.3389/fpls.2014.00432
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发表时间：
2014
影响因子：
5.6
通讯作者：
Hensel G
中科院分区：
文献类型：
--
作者：
Krupinska K;Oetke S;Desel C;Mulisch M;Schäfer A;Hollmann J;Kumlehn J;Hensel G
WHIRLY 1是叶绿体类核蛋白中的一个丰富蛋白，由于其在转录活性染色体（TAC）蛋白质组中的检测，也被命名为pTAC-1。在大麦初生叶中，WHIRLY 1基因在基部表达量最高，而蛋白质积累量最高的部位是叶片中部，那里有发育中的叶绿体。为了阐明WHIRLY 1在叶绿体类核中的功能，我们构建了一个RNAi介导的HvWHIRLY 1基因敲低的转基因大麦植株（RNAi-W1）。选择纯合RNAi-W1-7植物（几乎不含痕量的WHIRLY 1蛋白）用于详细分析类核。用YO-PRO®-1进行的核酸特异性染色显示，与具有连接到类囊体的多个小类核的野生型叶绿体相比，转基因植物的叶绿体除了类核之外还含有大小和形状与野生型叶绿体的类核相似的大的不规则形成的DNA片。在大的电子透明区，丝状结构检测到传统的透射电子显微镜。通过DNA斑点杂交和定量PCR对ptDNA水平的分析表明，转基因植物的叶片具有比野生型高2 - 3倍的ptDNA水平。在RNAi-W1植物中较高的ptDNA水平与在初级叶中部编码推定的细胞器靶向DNA聚合酶的基因的增强表达相一致。此外，大麦WHIRLY 1基因在E.大肠杆菌细胞揭示了细菌类核的更高的压缩。这些结果表明，WHIRLY 1属于组的质体类核相关蛋白（ptNAP）具有压缩叶绿体类核的亚群，从而影响DNA复制的功能。
WHIRLY1 is an abundant protein of chloroplast nucleoids, which has also been named pTAC-1 with regard to its detection in the proteome of transcriptionally active chromosomes (TAC). In barley primary foliage leaves, expression of the WHIRLY1 gene is highest at the base whereas protein accumulation is highest in the middle of the leaf where young developing chloroplasts are found. In order to elucidate the function of WHIRLY1 in chloroplast nucleoids, transgenic barley plants with an RNAi-mediated knock-down of the HvWHIRLY1 gene (RNAi-W1) were generated. The homozygous RNAi-W1-7 plants, barely containing traces of the WHIRLY1 protein, were chosen for detailed analyses of nucleoids. Nucleic acid specific-staining with YO-PRO®-1 revealed that in comparison to wild type chloroplasts, which have multiple small nucleoids attached to thylakoids, chloroplasts of the transgenic plants contain large irregularly formed patches of DNA besides nucleoids that are similar in size and shape to those of wild type chloroplasts. In large electron lucent areas, filamentous structures were detected by conventional transmission electron microscopy. Analyses of ptDNA levels by both DNA dot-blot hybridization and quantitative PCR showed that leaves of the transgenic plants have a two- to three-fold higher level of ptDNA than the wild type. The higher ptDNA level in RNAi-W1 plants coincided with an enhanced expression of the gene encoding a putative organelle targeted DNA polymerase in the mid part of primary foliage leaves. Furthermore, overexpression of the barley WHIRLY1 gene in E. coli cells revealed a higher compaction of bacterial nucleoids. These results suggest that WHIRLY1 belongs to the group of plastid nucleoid associated proteins (ptNAP) having a function in compacting a subpopulation of chloroplast nucleoids thereby affecting DNA replication.
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影响因子：
14.9
作者：
Hunter S;Jones P;Mitchell A;Apweiler R;Attwood TK;Bateman A;Bernard T;Binns D;Bork P;Burge S;de Castro E;Coggill P;Corbett M;Das U;Daugherty L;Duquenne L;Finn RD;Fraser M;Gough J;Haft D;Hulo N;Kahn D;Kelly E;Letunic I;Lonsdale D;Lopez R;Madera M;Maslen J;McAnulla C;McDowall J;McMenamin C;Mi H;Mutowo-Muellenet P;Mulder N;Natale D;Orengo C;Pesseat S;Punta M;Quinn AF;Rivoire C;Sangrador-Vegas A;Selengut JD;Sigrist CJ;Scheremetjew M;Tate J;Thimmajanarthanan M;Thomas PD;Wu CH;Yeats C;Yong SY
通讯作者：
Yong SY
影响因子：
2.9
作者：
FLING, SP;GREGERSON, DS
通讯作者：
GREGERSON, DS
影响因子：
4.3
作者：
Hensel, Goetz;Valkov, Vladimir;Kumlehn, Jochen
通讯作者：
Kumlehn, Jochen
影响因子：
3.5
作者：
Krause, K;Kilbienski, I;Krupinska, K
通讯作者：
Krupinska, K
影响因子：
5.3
作者：
Kohl S;Hollmann J;Blattner FR;Radchuk V;Andersch F;Steuernagel B;Schmutzer T;Scholz U;Krupinska K;Weber H;Weschke W
通讯作者：
Weschke W