The evolutionary relationship of the transcriptionally active fabp11a (intronless) and fabp11b genes of medaka with fabp11 genes of other teleost fishes

Abstract

Here we describe the structure of the fatty acid-binding protein 11a and 11b genes (fabp11a and fabp11b) in medaka, and their evolutionary relationship to fabp11 genes from other teleost fishes. Initial studies indicated that the medaka fabp11a gene is intronless, but the fabp11b gene consists of four exons separated by three introns, a genomic organization that is characteristic of most members of the intracellular lipid-binding protein family. Based on genomic sequence, we conclude that the intronless fabp11a gene most likely arose as a result of reverse transcription of its mRNA transcript into cDNA followed by integration into chromosomal DNA. The ancestral intron-containing fabp11a gene was presumably lost from the medaka genome. The duplicated fabp11 genes extant in medaka encode polypeptides of 134 amino acids, which share highest sequence identity and similarity, and cluster in a distinct phylogenetic clade, with their orthologs in other teleost fishes. The fabp11a and fabp11b genes in medaka are therefore orthologs of the fabp11a and fabp11b genes, respectively, of other teleost fishes. No conserved gene synteny was found between medaka fabp11a and fabp11a genes from other teleost fishes, supporting our suggestion as to how this intronless gene arose. However, conserved gene synteny was evident between medaka fabp11b and fabp11b genes from other teleost fishes. The tissue-specific distribution of transcripts for medaka and zebrafish fabp11a and fabp11b genes revealed acquisition of a new function(s) in various tissues by the medaka fabp11b gene, which may explain the retention of sister duplicates of fabp11 in the medaka genome.

Transcriptomic Changes during Previtellogenic and Vitellogenic Stages of Ovarian Development in Wreckfish (Hāpuku), Polyprion oxygeneios (Perciformes)

“…The particular FABP gene identified in this study was originally reported in the heart of long-fingered ice fish (Cryodraco antarticus) [36] but is nowadays more commonly referred to as teleost-specific fatty-acid binding protein-11 (fabp11) [37]. Interestingly, duplicate genes (fabp11a and fabp11b) have been identified in zebrafish, three-spined stickleback (Gasterosteus aculeatus), fugu (Takifugu rubripes), spotted green pufferfish (Tetraodon nigroviridis), medaka (Oryzias latipes) [38], and rainbow trout (Oncorhynchus mykiss) [35].…”

“…Despite the limited information about both membrane-bound and cytoplasmic FABPs in the ovary of fish [2], these proteins are thought to act as regulators of fatty-acid metabolism and of bioavailability by facilitating the transport of long-chain fatty acids through the cytoplasm to the site of their oxidation. FABPs are also thought to facilitate fatty acid transport for further lipid-signalling pathways as well as support overall lipid homeostasis [2,35,[38][39][40].…”

Transcriptome analysis of skin color variation during and after overwintering of Malaysian red tilapia

“…Aqp3 can reduce the differentiation and inhibit the apoptosis of stem cells in human through reducing the expressions of related genes in Wnt/GSK-3 β/β-catenin pathway (Liu et al, 2020). Fabp11a were probably involved in cellular uptake and transport of fatty acids, targeting of fatty acids to transport systems and several signalling pathways in Oryzias latipes (Parmar et al, 2012). In this study, all of these genes expression suggested that skin color variation of red tilapia during overwintering might be related to the proliferation, migration and differentiation of melanocytes.…”

Genome-Wide Analysis of the FABP Gene Family in Liver of Chicken (Gallus gallus): Identification, Dynamic Expression Profile, and Regulatory Mechanism

“…Atotal of 12 FABP genes have been identified in vertebrates until now, but not all members of FABP genes occur in the same species [4]. For example, FABP10 and FABP11 have only been proposed in nonmammalian vertebrates, like teleost fishes [5], while FABP12 appears restricted to mammals, such as human [6]. All vertebrate FABP genes possess four exons separated by three introns [7], and contain a classical three-element finger print domain shared by three motifs termed FATTYACIDBP 1-3 (Kyoto Encyclopedia of Genes and Genomes; PRINTS: PR00178) [8].…”