Deiodinase type II and tissue specific mRNA alternative splicing in the Australian lungfish, Neoceratodus forsteri

When the liver is disaggregated and hepatocytes are cultured as a cellular monolayer for 24 h, a sharp decline (80 to 99% decrease) in the transcription of most liver-specific mRNAs, but not common mRNAs, occurs (Clayton and Darnell, Mol. Cell. Biol. 2:1552-1561, 1983). A wide variety of culture conditions involving various hormones and substrates and cocultivation with other cells failed to sustain high rates of liver-specific mRNA synthesis in cultured hepatocytes, although they continued to synthesize common mRNAs at normal or elevated rates. In contrast, when slices of intact mouse liver tissue were placed in culture, the transcription of liver-specific genes was maintained at high levels (20 to 100% of normal liver). Furthermore, we found that cells in the liver could be disengaged and immediately reengaged in a tissue-like structure by perfusing the liver with EDTA followed by serum-containing culture medium. Slices of reengaged liver continued to transcribe tissue-specific mRNA sequences at significantly higher rates after 24 h in culture than did individual cells isolated by EDTA perfusion followed by culturing as a monolayer. Therefore we conclude that a mature tissue structure plays an important role in the maintenance of maximum tissue-specific transcription in liver cells.

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Evidence for tissue-specific alternative splicing of the ovine insulin receptor gene

Proceedings of the British Society of Animal Science ◽

10.1017/s1752756200597488 ◽

1998 ◽

Vol 1998 ◽

pp. 96-96

Author(s):

P.D. McGrattan ◽

A.R.G. Wylie ◽

A.J. Bjourson

Keyword(s):

Alternative Splicing ◽

Insulin Receptor ◽

Receptor Gene ◽

Protein Isoforms ◽

Common Mechanism ◽

Mrna Transcript ◽

Insulin Receptor Gene ◽

Tissue Specific ◽

Specific Regulation ◽

Exon 11

Alternative splicing of a discrete 36 base pair segment (exon 11) of the human and rat insulin receptor leads to the formation of high and low affinity isoforms differing as much as 3-fold in affinity for insulin. Alternative splicing is a common mechanism for generating protein isoforms and is often regulated in a tissue-specific fashion (Seino & Bell, 1989; Mosthaf et al., 1990). In humans, the lower affinity (B-isoform) mRNA transcript is predominantly expressed in tissues that are important for modulating glucose homeostasis such as the liver and muscle whereas the higher affinity (A-isoform) mRNA transcript is predominantly expressed in haematopoietic tissues such as spleen. Alternative splicing of the region of the ovine insulin receptor gene encoding exon 11 has recently been demonstrated (McGrattan et al., unpublished). The objective of the present study was to establish whether tissue-specific regulation of alternative splicing of the insulin receptor gene occurs in the ruminant animal.

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The complexity of alternative splicing and landscape of tissue-specific expression in lotus (Nelumbo nucifera) unveiled by Illumina- and single-molecule real-time-based RNA-sequencing

DNA Research ◽

10.1093/dnares/dsz010 ◽

2019 ◽

Vol 26 (4) ◽

pp. 301-311 ◽

Cited By ~ 11

Author(s):

Yue Zhang ◽

Tonny Maraga Nyong'A ◽

Tao Shi ◽

Pingfang Yang

Keyword(s):

Alternative Splicing ◽

Real Time ◽

Single Molecule ◽

Intron Retention ◽

Critical Role ◽

Full Length ◽

Specific Expression ◽

Splice Isoforms ◽

Tissue Specific ◽

Genomic Studies

Abstract Alternative splicing (AS) plays a critical role in regulating different physiological and developmental processes in eukaryotes, by dramatically increasing the diversity of the transcriptome and the proteome. However, the saturation and complexity of AS remain unclear in lotus due to its limitation of rare obtainment of full-length multiple-splice isoforms. In this study, we apply a hybrid assembly strategy by combining single-molecule real-time sequencing and Illumina RNA-seq to get a comprehensive insight into the lotus transcriptomic landscape. We identified 211,802 high-quality full-length non-chimeric reads, with 192,690 non-redundant isoforms, and updated the lotus reference gene model. Moreover, our analysis identified a total of 104,288 AS events from 16,543 genes, with alternative 3ʹ splice-site being the predominant model, following by intron retention. By exploring tissue datasets, 370 tissue-specific AS events were identified among 12 tissues. Both the tissue-specific genes and isoforms might play important roles in tissue or organ development, and are suitable for ‘ABCE’ model partly in floral tissues. A large number of AS events and isoform variants identified in our study enhance the understanding of transcriptional diversity in lotus, and provide valuable resource for further functional genomic studies.

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A putative growth-related renal Na(+)-Pi cotransporter

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1997.273.3.r928 ◽

1997 ◽

Vol 273 (3) ◽

pp. R928-R933 ◽

Cited By ~ 7

Author(s):

D. M. Silverstein ◽

M. Barac-Nieto ◽

H. Murer ◽

A. Spitzer

Keyword(s):

Renal Cortex ◽

Young Animal ◽

Subtractive Hybridization ◽

Type Ii ◽

Chain Reaction ◽

Adult Rats ◽

Subtraction Hybridization ◽

Adult Rat ◽

Polymerase Chain ◽

Specific Mrna

The mRNA that encodes for NaPi-2, the renal Na(+)-Pi cotransporter that is upregulated by Pi depletion in the adult rat, is low in the young animal. Yet, renal Na-Pi cotransport rates are higher in rapidly growing than in fully grown rats. The aim of this study was to unravel the molecular basis of this apparent discrepancy. Poly(A) RNA obtained from the renal cortex of young animals induced higher rates of Na(+)-Pi cotransport in oocytes than equal amounts of poly(A) mRNA obtained from the renal cortex of mature rats. Moreover, poly(A) RNA obtained from renal cortex of rapidly growing animals treated with antisense NaPi-2 oligomers or depleted of NaPi-2 transcripts by subtractive hybridization with cDNA generated from the renal cortex of adult rats retained its ability to induce Na(+)-Pi cotransport in oocytes. In addition, renal poly(A) RNA of the young subjected to subtraction hybridization generated a 379-base pair reverse transcriptase-polymerase chain reaction product common to all known type II Na(+)-Pi cotransporters. These observations permit us to surmise that the high rates of Na(+)-Pi cotransport prevailing during growth are due, at least in part, to the expression of a specific mRNA that is only partially homologous to that of NaPi-2.

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