Dual-specificity tyrosine phosphorylation-regulated kinases (DYRKs) are activated via the auto-phosphorylation of conserved tyrosine residues in their activation loop during protein translation, and they then phosphorylate serine/threonine residues on substrates. The DYRK family is widely conserved in eukaryotes and is composed of six subgroups. In plant lineages, DYRK homologs are classified into four subgroups, DYRK2s, yet another kinase1s, pre-mRNA processing factor 4 kinases, and DYRKPs. Only the DYRKP subgroup is plant-specific and has been identified in a wide array of plant lineages, including land plants and green algae. It has been suggested that in Arabidopsis thaliana DYRKPs are involved in the regulation of centripetal nuclear positioning induced by dark light conditions. However, the molecular functions, such as kinase activity and the developmental and physiological roles of DYRKPs are poorly understood. Here, we focused on a sole DYRKP ortholog in the model bryophyte, Marchantia polymorpha, MpDYRKP. MpDYRKP has a highly conserved kinase domain located in the C-terminal region and shares common sequence motifs in the N-terminal region with other DYRKP members. To identify the roles of MpDYRKP in M. polymorpha, we generated loss-of-function Mpdyrkp mutants via genome editing. Mpdyrkp mutants exhibited abnormal, shrunken morphologies with less flattening in their vegetative plant bodies, thalli, and male reproductive organs, antheridial receptacles. The surfaces of the thalli in the Mpdyrkp mutants appeared uneven and disordered. Moreover, their epidermal cells were drastically altered to a narrower shape when compared to the wild type. These results suggest that MpDYRKP acts as a morphological regulator, which contributes to orderly tissue morphogenesis via the regulation of cell shape.

双特异性酪氨酸磷酸化调节激酶 (DYRK) 在蛋白质翻译过程中通过其激活环中保守酪氨酸残基的自身磷酸化而被激活，然后它们磷酸化底物上的丝氨酸/苏氨酸残基。 DYRK 家族在真核生物中广泛保守，由六个亚群组成。在植物谱系中，DYRK 同源物分为四个亚组：DYRK2、另一种激酶1、前 mRNA 加工因子 4 激酶和 DYRKP。只有 DYRKP 亚组是植物特异性的，并且已在多种植物谱系中得到鉴定，包括陆地植物和绿藻。有人提出，在拟南芥中，DYRKP 参与暗光条件诱导的向心核定位的调节。然而，人们对 DYRKP 的分子功能（例如激酶活性以及发育和生理作用）知之甚少。在这里，我们重点关注模式苔藓植物地钱中唯一的 DYRKP 直系同源物，MpDYRKP。 MpDYRKP 在 C 端区域具有高度保守的激酶结构域，并与其他 DYRKP 成员在 N 端区域共享共同的序列基序。为了确定 MpDYRKP 在地钱花中的作用，我们通过基因组编辑生成了功能丧失的 Mp dyrkp突变体。 Mp dyrkp突变体的营养植物体、菌体和雄性生殖器官、花药容器表现出异常、萎缩的形态，扁平化程度较低。 Mp dyrkp突变体的菌体表面显得不均匀且无序。此外，与野生型相比，它们的表皮细胞形状发生了巨大变化，变得更窄。 这些结果表明 MpDYRKP 作为形态调节剂，通过细胞形状的调节有助于有序的组织形态发生。