Polysome profiling reveals translational control of gene expression in the human malaria parasite Plasmodium falciparum

Table 2 Number of translationally delayed genes for selected groups of parasite-specific proteins

			Average normalized read count per 1 kb exon (delay)			Average normalized read count per 1 kb exon (no delay)
Group	Delay^a( n)	Delay to R stage^b( n)	Steady-state mRNA	Polysomal mRNA	No delay ( n)	Steady-state mRNA	Polysomal mRNA	P-value^c
FIKK kinase family	8	2	113	25	8	232	30	-
MC-2TM	7	7	39	18	4	209	72	0.0027
RESA-like protein	2	1	23	9	2	71	12	-
Plasmepsin	5	3	251	40	3	1,913	113	-
Exported proteins	47	31	559	66	71	1,234	258	<0.001
ApiAP2 transcription factor	7	1	354	67	11	353	28	-
Apicoplast-encoded proteins	11	11	110	97	0	NA	NA	<0.001
Apicoplast-targeted proteins	120	50	420	90	255	969	283	-
Conserved proteins, unknown function	565	237	340	89	1,132	514	166	-
Total^d	1,280	471	515	114	2,727	832	216	NA

^aDefined as at least 18 h delay in peak abundance levels in polysomal mRNA as compared to steady-state mRNA.
^bSubset of delayed genes, showing peak steady-state mRNA abundance in the trophozoite or schizont stage and peak polysomal mRNA abundance in the ring stage.
^cBonferroni-corrected two-tailed Fisher’s exact test for number of genes showing translational delay to the ring stage versus the number of non-delayed genes per group. P-values >0.01 are indicated with a dash.
^dTotal number of expressed and cell-cycle regulated genes included in our analysis.
NA., not applicable.

ISSN: 1474-760X