Identification of dyneins that localize exclusively to the proximal portion of Chlamydomonas flagella
Identification of dyneins that localize exclusively to the proximal portion of Chlamydomonas flagella
复制标题
DOI：
10.1242/jcs.045096
复制
发表时间：
2009-05-01
影响因子：
4
通讯作者：
Kamiya, Ritsu
中科院分区：
文献类型：
--
作者：
Yagi, Toshiki;Uematsu, Keigo;Kamiya, Ritsu
纤毛和鞭毛的运动是由多种动力蛋白重链驱动的，它们构成了动力蛋白的内臂和外臂。在衣藻属中，已在轴丝中鉴定出11个DHC蛋白，但在基因组中存在14个编码轴丝DHC的基因。在这里，我们将每个先前未分配的DHC基因分配给一个特定的DHC蛋白，并发现DHC 3、DH4和DH11编码新的、相对低丰度的DHC。免疫荧光显微镜显示，该基因仅定位于鞭毛的近端，与长约12微米的鞭毛相似，接近2微米。对生长鞭毛的分析表明，dh3和dhs4也定位于近端。相比之下，以前发现的臂内动力蛋白dynein b的DHC呈现出相反的分布模式。因此，鞭毛轴丝近端的动力蛋白组成明显不同于其余部分，这种差异可能与鞭毛底部执行的特殊功能有关。
The movements of cilia and flagella are driven by multiple species of dynein heavy chains (DHCs), which constitute inner- and outer-dynein arms. In Chlamydomonas, 11 DHC proteins have been identified in the axoneme, but 14 genes encoding axonemal DHCs are present in the genome. Here, we assigned each previously unassigned DHC gene to a particular DHC protein and found that DHC3, DHC4 and DHC11 encode novel, relatively low abundance DHCs. Immunofluorescence microcopy revealed that DHC11 is localized exclusively to the proximal similar to 2 mu m region of the similar to 12 mu m long flagellum. Analyses of growing flagella suggested that DHC3 and DHC4 are also localized to the proximal region. By contrast, the DHC of a previously identified inner-arm dynein, dynein b, displayed an inverse distribution pattern. Thus, the proximal portion of the flagellar axoneme apparently differs in dynein composition from the remaining portion; this difference might be relevant to the special function performed by the flagellar base.