The family of maize D‐type cyclins: genomic organization, phylogeny and expression patterns

Abstract

Cyclin proteins, associated to cyclin-dependent kinases (CDKs), play fundamental roles in cell cycle control as they constitute a very important driving force to allow cell cycle progression. D-type cyclins (CycDs) are important both for interpreting external mitogenic signals and in the control of the G1 phase. The maize (Zea mays) genome appears to contain at least 17 different CycD genes, and they fall into the subgroups previously described for other plants. Maize CycDs have been named according to identity percentages of the corresponding orthologs in rice and Arabidopsis. In silico analysis confirmed the presence of characteristic cyclin domains in each maize CycD gene and showed that their genomic organization is similar to their orthologs in rice and Arabidopsis. The expression of maize CycD genes was followed in seeds, during germination in the presence/absence of exogenously added hormones, and also in different plantlet tissues (mesocotyl, root tips and first leaf). Most cyclins were expressed in germinating seeds and at least in one of the plantlet tissues tested; almost all of the detected cyclins show an accumulating pattern of mRNA along germination (0-24 h) and higher levels in root tissue. Interestingly, some cyclins show high levels in non-proliferating tissues as leaf. Addition of auxins or cytokinins does not seem to importantly modify transcript levels; on the other hand, addition of abscisic acid repressed the expression of several cyclins. The role of each CycD during germination and plant growth and its interaction with other cell cycle proteins becomes a topic of the highest interest.

Complexes of D-type cyclins with CDKs during maize germination

“…Maize cells contain 17 genes that encode D-type cyclins, and 15 of them are expressed during germination (Buendía-Monreal et al , 2011). To study the expression at the protein level, and their function during maize germination, antibodies against CycD4;2 or against CycD5;3 were used; the anti-CycD4;2 antibody recognized a 41kDa protein that was present in embryo axes of dry seeds and levels peaked at 18h of germination, to be reduced to about half that value at 24h (Fig.…”

“…Maize cells contain 17 different genes coding for D-type cyclins, 15 of which are expressed during germination (Buendía-Monreal et al , 2011); three of them have also been studied at the protein level (Gutiérrez et al , 2005; Lara-Núñez et al , 2008). The aim of this work was to study complexes formed by three maize cyclins—CycD2;2 (a or b, 94% identical), CycD4;2, and CycD5;3 (a or b, 74% identical) with CDKs (types A and B1;1) during the early stages of maize germination, following D-type cyclin protein levels, the type of complexes formed between different cyclins and CDKs, and their activity during maize germination.…”

Zygotic Genome Activation Occurs Shortly after Fertilization in Maize

“…edu/annotation_pseudo_apk.shtml). Predicted cyclins (Hu et al, 2010) were added to the list, as well as genes reported to be involved in cell cycle regulation in previous publications (Sauter et al, 1998;Dresselhaus et al, 1999bDresselhaus et al, , 2006Buendía-Monreal et al, 2011;Dante et al, 2014). Finally, the DNA replication-indicating genes encoding proliferating cell nuclear antigen and MCM homologous proteins were added to the list manually based on Ensemble plants (www.plants.ensemble.org) (Sabelli et al, 2009).…”

Identification and functional analysis of the ICK gene family in maize

“…All related genes were first cloned using KOD enzymes (Toyobo, Osaka, Japan). The maize cell cycle genes, D-type cyclins (AF351190.1; AF351189.141), A-type CDKs (M60526.1, ZmCDKA1; GRMZM2G143213, ZmCDKA2 42; GRMZM2G174596, ZmCDKA336), and B-type CDK (GRMZM2G495626)36) were cloned from the cDNA using gene-specific primers containing NdeI and BamHI restriction sites. The putative ICK/KRP genes were cloned with primers containing NdeI and SalI restriction sites (Table S3).…”