The identification of new cytosolic glutamine synthetase and asparagine synthetase genes in barley (Hordeum vulgare L.), and their expression during leaf senescence.
The identification of new cytosolic glutamine synthetase and asparagine synthetase genes in barley (Hordeum vulgare L.), and their expression during leaf senescence.
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DOI：
10.1093/jxb/erv003
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发表时间：
2015-04
影响因子：
6.9
通讯作者：
Masclaux-Daubresse C
中科院分区：
文献类型：
--
作者：
Avila-Ospina L;Marmagne A;Talbotec J;Krupinska K;Masclaux-Daubresse C
大麦基因组中鉴定出的 5 个 HvGS1 和 5 个 HvASN 基因在大麦叶片中的表达存在差异，具体取决于衰老、氮状况和黑暗暴露。谷氨酰胺合成酶和天冬酰胺合成酶是植物中参与铵同化的两种主要酶。已经提出了它们在氮再动员和氮利用效率中的作用。在本报告中，鉴定了大麦中编码胞质谷氨酰胺合成酶 (HvGS1) 和天冬酰胺合成酶 (HvASN) 的基因。除了先前报道的三个 HvGS1 和两个 HvASN 序列外，还鉴定了两个原核样 HvGS1 和三个 HvASN cDNA 序列。然后对基因结构进行表征，获得完整的基因组序列。然后研究了五个 HvGS1 和五个 HvASN 基因对叶片衰老的响应。使用初生叶和旗叶研究发育衰老。黑暗暴露或低硝酸盐条件也被用来引发压力诱导的衰老。为了表征不同叶子的衰老水平，我们对叶绿素和 Rubisco 含量等众所周知的衰老标志物进行了监测。三个类真核 HvGS1_1、HvGS1_2 和 HvGS1_3 序列显示出许多植物物种中典型的衰老诱导的基因表达减少。相比之下，两个原核样 HvGS1_4 和 HvGS1_5 序列受到叶片衰老的抑制，类似于编码叶绿体谷氨酰胺合成酶同工酶的 HvGS2 基因。五个 HvASN 的反应存在较大差异，这表明只有当植物充分施硝酸盐时，衰老叶子中的氮再动员才需要这些基因。 HvASN 序列对黑暗诱导衰老的反应表明，有两类天冬酰胺合成酶，一类在黑暗中诱导，另一类在相同条件下受到抑制。
The five HvGS1 and five HvASN genes identified in the barley genome are differentially expressed in barley leaves depending on senescence, nitrogen regime, and dark exposure. Glutamine synthetase and asparagine synthetase are two master enzymes involved in ammonium assimilation in plants. Their roles in nitrogen remobilization and nitrogen use efficiency have been proposed. In this report, the genes coding for the cytosolic glutamine synthetases (HvGS1) and asparagine synthetases (HvASN) in barley were identified. In addition to the three HvGS1 and two HvASN sequences previously reported, two prokaryotic-like HvGS1 and three HvASN cDNA sequences were identified. Gene structures were then characterized, obtaining full genomic sequences. The response of the five HvGS1 and five HvASN genes to leaf senescence was then studied. Developmental senescence was studied using primary and flag leaves. Dark-exposure or low-nitrate conditions were also used to trigger stress-induced senescence. Well-known senescence markers such as the chlorophyll and Rubisco contents were monitored in order to characterize senescence levels in the different leaves. The three eukaryotic-like HvGS1_1, HvGS1_2, and HvGS1_3 sequences showed the typical senescence-induced reduction in gene expression described in many plant species. By contrast, the two prokaryotic-like HvGS1_4 and HvGS1_5 sequences were repressed by leaf senescence, similar to the HvGS2 gene, which encodes the chloroplast glutamine synthetase isoenzyme. There was a greater contrast in the responses of the five HvASN and this suggested that these genes are needed for N remobilization in senescing leaves only when plants are well fertilized with nitrate. Responses of the HvASN sequences to dark-induced senescence showed that there are two categories of asparagine synthetases, one induced in the dark and the other repressed by the same conditions.
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影响因子：
7.4
作者：
Diaz, Celine;Lemaitre, Thomas;Masclaux-Daubresse, Celine
通讯作者：
Masclaux-Daubresse, Celine
影响因子：
4.3
作者：
Brugière, N;Dubois, F;Hirel, B
通讯作者：
Hirel, B
影响因子：
7.2
作者：
Hanson, Johannes;Hanssen, Micha;Smeekens, Sjef
通讯作者：
Smeekens, Sjef
影响因子：
5.1
作者：
Gregersen, Per L.;Culetic, Andrea;Krupinska, Karin
通讯作者：
Krupinska, Karin
影响因子：
4.9
作者：
Lemaitre, Thomas;Gaufichon, Laure;Masclaux-Daubresse, Celine
通讯作者：
Masclaux-Daubresse, Celine