Ikaros is a member of the Kruppel family of zinc finger DNA-binding proteins. The Ikaros protein contains two separate regions of zinc-finger domains: 4 DNA-binding zinc fingers near the N-terminus and 2 zinc fingers for protein-protein interactions near the C-terminus. Here, we identified the Ikaros gene from 14 vertebrate genomes and found Ikaros existed in all kinds of vertebrate including fish, amphibians, birds and mammals. Moreover, except rat and Xenopus tropicalis Ikaros proteins, which lack the first C2H2-type 1 Zinc finger region, all identified Ikaros proteins contain six C2H2-type 1 Zinc finger regions. We found human Ikaros gene showed a predominant expression in the liver, lymph node, thymus, intestine, lung, mammary gland, bone marrow, brain, heart, placenta and prostate. Moreover, four available SNPs disrupted an existing exonic splicing enhancer were identified in Ikaros. Besides the reported acute lymphoblastic leukemia (ALL), the expression of Ikaros was related to the prognosis of 13 cases of cancers including blood cancers, breast, lung, ovarian and skin cancer. Moreover, the relationship between the expression of Ikaros and prognosis varied in different cancers, even in the same cancer from different database. Two tumor-related transcriptional factor (c-Fos and Elk-1) binding sites were identified within the 1.5-kb regions upstream of the transcriptional start site of human Ikaros, which may be involved in the effect of Ikaros in tumors.

Loquat (Eriobotrya japonica Lindl.) is an important non-climacteric fruit and rich in essential nutrients such as minerals and carotenoids. During fruit development and ripening, thousands of the differentially expressed genes (DEGs) from various metabolic pathways cause a series of physiological and biochemical changes. To better understand the underlying mechanism of fruit development, the Solexa/Illumina RNA-seq high-throughput sequencing was used to evaluate the global changes of gene transcription levels. More than 51,610,234 high quality reads from ten runs of fruit development were sequenced and assembled into 48,838 unigenes. Among 3256 DEGs, 2304 unigenes could be annotated to the Gene Ontology database. These DEGs were distributed into 119 pathways described in the Kyoto Encyclopedia of Genes and Genomes (KEGG) database. A large number of DEGs were involved in carbohydrate metabolism, hormone signaling, and cell-wall degradation. The real-time reverse transcription (qRT)-PCR analyses revealed that several genes related to cell expansion, auxin signaling and ethylene response were differentially expressed during fruit development. Other members of transcription factor families were also identified. There were 952 DEGs considered as novel genes with no annotation in any databases. These unigenes will serve as an invaluable genetic resource for loquat molecular breeding and postharvest storage.