Glucose and sucrose differentially modify cell proliferation in maize during germination.
Glucose and sucrose play a dual role: as carbon and energy sources and as signaling molecules. In order to address the impact that sugars may have on maize seeds during germination, embryo axes were incubated with or without either of the two sugars. Expression of key cell cycle markers and protein abundance, cell patterning and de novo DNA synthesis in root meristem zones were analyzed. Embryo axes without added sugars in imbibition medium were unable to grow after 7 days; in sucrose, embryo axes developed seminal and primary roots with numerous root hairs, whereas in glucose axes showed a twisted morphology, no root hair formation but callus-like structures on adventitious and primary seminal roots. More and smaller cells were observed with glucose treatment in root apical meristems. de novo DNA synthesis was stimulated more by glucose than by sucrose. At 24 h of imbibition, expression of ZmCycD2;2a and ZmCycD4;2 was increased by sucrose and reduced by glucose. CDKA1;1 and CDKA2;1 expression was stimulated equally by both sugars. Protein abundance patterns were modified by sugars: ZmCycD2 showed peaks on glucose at 12 and 36 h of imbibition whereas sucrose promoted ZmCycD3 protein accumulation. In presence of glucose ZmCycD3, ZmCycD4 and ZmCycD6 protein abundance was reduced after 24 h. Finally, both sugars stimulated ZmCDKA protein accumulation but at different times. Overall, even though glucose appears to act as a stronger mitogen stimulator, sucrose stimulated the expression of more cell cycle markers during germination. This work provides evidence of a differential response of cell cycle markers to sucrose and glucose during maize germination that may affect the developmental program during plantlet establishment.
Facultad de Química, Departamento de Bioquímica, Universidad Nacional Autónoma de México, Ciudad de México, Mexico. Electronic address: auroraln@unam.mx.
Aurora
A
Lara-Núñez
Facultad de Química, Departamento de Bioquímica, Universidad Nacional Autónoma de México, Ciudad de México, Mexico.
Brendy B
BB
García-Ayala
Facultad de Química, Departamento de Bioquímica, Universidad Nacional Autónoma de México, Ciudad de México, Mexico.
Sara M
SM
Garza-Aguilar
Facultad de Química, Departamento de Bioquímica, Universidad Nacional Autónoma de México, Ciudad de México, Mexico.
Jesús
J
Flores-Sánchez
Facultad de Química, Departamento de Bioquímica, Universidad Nacional Autónoma de México, Ciudad de México, Mexico.
Victor A
VA
Sánchez-Camargo
Facultad de Química, Departamento de Bioquímica, Universidad Nacional Autónoma de México, Ciudad de México, Mexico.
Carlos E
CE
Bravo-Alberto
Facultad de Ciencias, Departamento de Biología Comparada, Universidad Nacional Autónoma de México, Ciudad de México, Mexico.
Sonia
S
Vázquez-Santana
Facultad de Química, Departamento de Bioquímica, Universidad Nacional Autónoma de México, Ciudad de México, Mexico.
Jorge M
JM
Vázquez-Ramos
D002453:Cell Cycle / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D018844:Cyclin-Dependent Kinases / Q000096:biosynthesis; D016213:Cyclins / Q000187:drug effects; D018744:DNA, Plant / Q000096:biosynthesis; D018525:Germination / Q000187:drug effects*; D005947:Glucose / Q000378:metabolism / Q000494:pharmacology* / Q000502:physiology; D063245:Plant Development / Q000187:drug effects; D010940:Plant Proteins / Q000096:biosynthesis; D018517:Plant Roots / Q000166:cytology / Q000187:drug effects; D012639:Seeds / Q000166:cytology / Q000187:drug effects; D013395:Sucrose / Q000378:metabolism / Q000494:pharmacology*; D003313:Zea mays / Q000166:cytology / Q000187:drug effects* / Q000196:embryology
D016213:Cyclins; D018744:DNA, Plant; D010940:Plant Proteins; D013395:Sucrose; D018844:Cyclin-Dependent Kinases; D005947:Glucose
CDKs; Cell cycle; Cyclins; Germination; Glucose; Maize; Sucrose