Mechanism Of Action Of Lectin Receptor Like Kinase LecRK?.1 And LecRK?.2 Genes In Arabidopsis Thaliana

Receptor like kinase (RLK) gene family plays an important role in sensing and transducing extracellular signals. This family has an important function in plant growth, development as well as biological and abiotic stress responses. Among this family a group named lectin receptor kinase (LecRLK) is critical in plant immune, stress and hormone responses. Some members of this subfamily are also involved in pollen development process. Genes named LecRK?.l and LecRK?.2 are two members of LecRLK family by sequence alignment, but there is no related study about the two genes up to now.In the thesis, we found that the two genes LecRK?.1 and LecRK?.2 are typical LecRLK family members in structure by biological information analysis. They have an extracellular soy-like lectin domain, a single transmembrane domain in the middle, and an intracellular domain of serine/threonine kinase. There are varieties of light response elements, damage stress response elements and hormonal response elements, etc in the promoter regions of the two genes. The two genes express low in the whole plant cycle. All the results above show that the genes LecRK?.1 and LecRK?.2 can sense extracellular signals of stress and light. Sequence alignment of the two genes, shows that the genes LecRK?.1 and LecRK?.2 have a very high homology. Subcellular localization experiment verified the two genes were located in the cell membrane. The yeast two-hybrid and BIFC experiments showed the proteins LecRK?.l and LecRK?.2 function as homologous dimers. The experiment of screening of Arabidopsis cDNA library for the intracellular fragment of LecRK?.2 protein provided an important basis for further exploration of the two genes involved in signaling pathways. We identified three homozygous deletion mutants of the genes LecRK?.1 and LecRK?.2 named lecrklll.l-l, lecrklll.1-2 and lecrklll.2-1, and we constructed the over-expression line of gene LecRK?.2, which lay the foundation for further researches about biological functions of the two genes.