title: Molecular characterization and expression analysis of SERK1 and SERK2 in Brassica napus L.: implication for microspore embryogenesis and plant regeneration.
abstract: The BnSERK1 and BnSERK2 are involved in the process of microspore embryogenesis induction, development, and plantlet regeneration. Little is known about regulatory role of somatic embryogenesis-related kinase (SERK) genes family in the induction of microspore embryogenesis, development and plant regeneration. In this study, the expression of two SERK genes (SERK1 and SERK2) was assessed during the microspore embryogenesis and plantlet regeneration in Brassica napus L. The BnSERK1 was severely up-regulated 1-5 days following microspore culture and its expression drastically decreased in the globular-heart and also torpedo staged microspore-derived embryos (MDEs). In addition, high levels of BnSERK1 transcript were detected in the MDE maturation phase and in the roots and shoots of the regenerated plantlets which indicates a broader role(s) of BnSERK1 in the organ formation, rather than being specific to the embryogenesis. Results of partial sequencing indicated that the BnSERK1 shares a conserved serine-threonine kinase catalytic domain and exhibited 95 % similarity with AtSERK1, CsSERK1, BrSERK1, NaSERK1, and NbSERK1. A steady increase in the expression of BnSERK2 was observed during the MDE initiation and development so that, the highest expression was noted in the MDE maturation phase i.e., late cotyledonary MDEs. Our results also indicated low amounts of BnSERK2 transcript at the onset of rhyzogenesis but significantly higher expression in the developing roots. In contrast, the BnSERK2 strongly up-regulated during the both initially and developed shoots. The BnSERK2 shares highly conserved LRR-RLK domain when compared with different species tested so that, high homology (100 %) was noticed with BrSERK2. Based on our findings, MDE formation and plantlet regeneration seem to be correlated with both BnSERK1 and BnSERK2 expression.
authors.affiliation: Department of Tissue Culture and Gene Transformation, Agricultural Biotechnology Research Institute of Iran (ABRII), AREEO, 3135933151, Karaj, Iran.
authors.forename: Behzad
authors.initials: B
authors.lastname: Ahmadi
authors.affiliation: Department of Tissue Culture and Gene Transformation, Agricultural Biotechnology Research Institute of Iran (ABRII), AREEO, 3135933151, Karaj, Iran.
authors.forename: Farhad
authors.initials: F
authors.lastname: Masoomi-Aladizgeh
authors.affiliation: Department of Tissue Culture and Gene Transformation, Agricultural Biotechnology Research Institute of Iran (ABRII), AREEO, 3135933151, Karaj, Iran. mehran.shariatpanahi@abrii.ac.ir.
authors.forename: Mehran E
authors.initials: ME
authors.lastname: Shariatpanahi
authors.affiliation: Department of Tissue Culture and Gene Transformation, Agricultural Biotechnology Research Institute of Iran (ABRII), AREEO, 3135933151, Karaj, Iran.
authors.forename: Pejman
authors.initials: P
authors.lastname: Azadi
authors.affiliation: Department of Tissue Culture and Gene Transformation, Agricultural Biotechnology Research Institute of Iran (ABRII), AREEO, 3135933151, Karaj, Iran.
authors.forename: Mehdi
authors.initials: M
authors.lastname: Keshavarz-Alizadeh
mesh_terms: D029688:Brassica napus / Q000235:genetics* / Q000254:growth & development / Q000502:physiology; D020134:Catalytic Domain; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D058439:Plant Somatic Embryogenesis Techniques; D011058:Pollen / Q000235:genetics / Q000254:growth & development / Q000502:physiology; D011494:Protein Kinases / Q000235:genetics* / Q000378:metabolism; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism; D012038:Regeneration; D015854:Up-Regulation
chemical_list: D010940:Plant Proteins; D011494:Protein Kinases; C106294:SERK protein, plant; D017346:Protein Serine-Threonine Kinases
keywords: Brassica napus L.; DAPI; Microspore embryogenesis; SERK; qRT-PCR