Maurya Ranjana, Kumar Rakesh, Saran Shweta
School of Life Sciences, Jawaharlal Nehru University, New Delhi 110067, India.
School of Life Sciences, Jawaharlal Nehru University, New Delhi 110067, India
Open Biol. 2017 Jul;7(7). doi: 10.1098/rsob.170055.
Starved cells aggregate into groups of nearly 10 cells. AMPK is a highly conserved serine/threonine protein kinase consisting of a catalytic and two regulatory subunits. As multi-cellular development in is initiated upon starvation, we explored the role of the energy sensor, AMPK, which shows significant similarity to human AMPK and is expressed throughout development. Deletion of the gene results in the formation of numerous small-sized aggregates that develop asynchronously to form few fruiting bodies with small sori and long stalks. On the other hand, cells form fruiting bodies with small stalks and large sori when compared with wild-type, Ax2. A minimum of 5% cells in a chimaera with Ax2 cells was sufficient to reduce the aggregate size. Also, the conditioned media collected from cells triggered Ax2 cells to form smaller aggregates. The starved cells showed low glucose levels and formed large aggregates when glucose was supplied exogenously. Interestingly, cells exhibit abnormal cell-type patterning with increased prestalk region and a concomitant reduction of prespore region. In addition, there was a loss of distinct prestalk/prespore boundary in the slugs.
饥饿的细胞聚集成近10个细胞的群体。AMPK是一种高度保守的丝氨酸/苏氨酸蛋白激酶，由一个催化亚基和两个调节亚基组成。由于饥饿会引发多细胞发育，我们探究了能量传感器AMPK的作用，它与人类AMPK具有显著相似性，且在整个发育过程中都有表达。该基因的缺失会导致形成大量小尺寸聚集体，这些聚集体异步发育，形成少数带有小孢子囊和长柄的子实体。另一方面，与野生型Ax2相比，细胞形成的子实体柄短且孢子囊大。在与Ax2细胞形成的嵌合体中，至少5%的细胞足以减小聚集体的大小。此外，从细胞收集的条件培养基会促使Ax2细胞形成更小的聚集体。饥饿的细胞显示出低葡萄糖水平，当外源供应葡萄糖时会形成大聚集体。有趣的是，细胞表现出异常的细胞类型模式，前柄区域增加，同时前孢子区域减少。此外，蛞蝓中前柄/前孢子的明显边界消失。
