Table S1

Candidate gene qRT PCR primers and gene cloning and linkage primers"

Table S2

Analysis of physical and chemical properties of WD40 protein"

Fig. 1

Distribution of PgWD40 family members on chromosomes map"

Fig. S1

Analysis of the conservative domain, conserved motifs, and gene structure of the Ⅰ subfamily of PgWD40 gene family From left to right: (a) Evolution tree of WD40 gene family of Pennisetum americanum. (b) The motif distribution of WD40 protein in Pearl millet. The different colors on the right label represent different motifs. (c) The structure of representative PgWD40 protein. The protein structure is based on the existence of WD40 and the internal and external Substructure of 209 other domains (d) of Pennisetum americanum WD40 gene recognized by NCBI. Exons and introns are represented by yellow and green boxes, respectively; The yellow box represents CDS."

Fig. S2

Analysis of the conservative domain, conserved motifs, and gene structure of the Ⅱ subfamily of the PgWD40 gene family From left to right: (a) Evolution tree of WD40 gene family of Pennisetum americanum. (b) The motif distribution of WD40 protein in Pearl millet. The different colors on the right label represent different motifs. (c) The structure of representative PgWD40 protein. The protein structure is based on the existence of WD40 and the internal and external Substructure of 209 other domains (d) of Pennisetum americanum WD40 gene recognized by NCBI. Exons and introns are represented by yellow and green boxes, respectively; The yellow box represents CDS."

Fig. S3

Analysis of the conservative domain, conserved motifs, and gene structure of the Ⅲ to Ⅴ subfamilies of the PgWD40 gene family From left to right: (a) Evolution tree of WD40 gene family of Pennisetum americanum. (b) The motif distribution of WD40 protein in Pearl millet. The different colors on the right label represent different motifs. (c) The structure of representative PgWD40 protein. The protein structure is based on the existence of WD40 and the internal and external Substructure of 209 other domains (d) of Pennisetum Americanum WD40 gene recognized by NCBI. Exons and introns are represented by yellow and green boxes, respectively; The yellow box represents CDS."

Fig. 2

Conserved motif signature of the PgWD40 family proteins The numbers represent 10 different patterns and their codes. Colored letters represent the amino acid residue types in each motif sequence identifier."

Fig. S4

Analysis of cis-acting elements in the promoter sequences of PgWD40 genes The responsive elements in the promoter sequences of PgWD40 genes include abscisic acid, anaerobic induction, auxin response, jasmonic acid response, circadian rhythm regulation, gibberellin response, light response, hypoxia-specific induction, growth and development related elements, salicylic acid response, defense and stress response, drought induction, low temperature response, and wound response elements."

Fig. 3

Evolutionary tree of the WD40 gene family members in Pennisetum glaucum (Pg) and Oryza sativa (Os)"

Fig. 4

Synteny analysis of the PgWD40 gene family"

Fig. 5

Synteny analysis of the WD40 gene family in Pennisetum glaucum (Pg) and Oryza sativa (Os)"

Fig. 6

Expression heatmap of PgWD40 gene family members under salt stress “L” stands for leaf, “R” stands for root, and the numbers represent the duration of stress."

Fig. 7

Expression heatmap of PgWD40 gene family members under heat stress “L” stands for leaf, “R” stands for root, and the numbers represent the duration of stress."

Fig. 8

Expression heatmap of PgWD40 gene family members under drought stress “L” stands for leaf, “R” stands for root, and the numbers represent the duration of stress."

Fig. 9

Expression heatmap of PgWD40 gene family members in different parts The respective parts are as follows: HI_SP represents spikes at heading stage, FW_F represents spikes at flowering stage, SI_SD represents spikes at wax ripening stage, and seed represents fully ripened seeds."

Fig. 10

Expression analysis of PgWD40 gene family members under different stress conditions D: drought stress; H: heat stress; S: salt stress; the number after stress represents the duration of stress."

Fig. 11

Protein-protein interaction network of PgWD40 proteins Colorful spheres represent different proteins, and within each sphere is the corresponding three-dimensional structure of that protein. The connections between different proteins are specified as follows: Sky-blue line: obtained from curated databases; purple line: experimentally determined; green line: gene neighborhood; deep blue line: gene co-occurrence; light yellow line: text data mining; black line: co-expression; light blue line: protein homology translation."

Fig. 12

Gene Ontology (GO) analysis of PgWD40 gene family members The Gene Ontology (GO) analysis was conducted using the eggNOG online platform, and it was divided into three aspects: molecular function, biological process, and cellular component. The Y-axis represents specific GO categories, and the X-axis represents the corresponding protein sequence counts."

Fig. 13

KEGG analysis of PgWD40 gene family members"

Fig. 14

Tertiary structure analysis of eight PgWD40 proteins"

Fig. 15

Subcellular localization analysis of empty vector 2300, PMA4G00558.1, and PMA5G02217.1"