Structure and expression of the guinea-pig α-lactalbumin gene

Laird, J E; Jack, Lisa M.; Hall, Len; Boulton, A P; Parker, D; Craig, Roger K.

doi:10.1042/bj2540085

Cited by 44 publications

(14 citation statements)

References 45 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Moreover the promoters from a species can conveniently be employed in a heterologous species to express the desired protein. The characteristic tissue specific expression of promoters of mammary gland has been attributed to the particular promoter sequences, cis-acting elements, and tissue specific factors (Laird et al 1988). In addition to mammary gland specific factors, a number of ubiquitous nuclear factors have been shown to bind to several positions within the promoter region of the milk protein genes.…”

Section: Introductionmentioning

confidence: 99%

Cloning and characterization of ovine αS1-casein gene promoter: A transfection study in rat mammary gland cell line

Bhure

Sharma

2007

DNA Sequence

View full text Add to dashboard Cite

Promoter regions of milk protein genes are frequently used to produce pharmaceutically and medically important proteins in the mammary gland of transgenic animals and also can be used for the construction of an inducible eukaryotic expression vector. The aim of the present study was to clone, sequence and characterize the regulatory elements in ovine alphaS1-CSNGP. For the first time we have cloned and sequenced region extending from - 2136 to +49 bp containing 5'-flanking region and exon I. Computational analysis of the sequence showed presence of core promoter elements viz., TATA box, CAAT box and initiator sequence. Mammary gland specific sequences included MGF/STAT 5, MPBF, Yu Lee 2, 4 and 5, Oka box C and hormone responsive elements (HRE) viz., GRE, PRE, PRL, IRE and also Polyoma enhancer 3 sequences. Computational analysis data is validated by following the reporter gene expression studies in rat breast cell line. Six reporter gene constructs under the control of full length, proximal, distal, minimal and proximal-distal fused promoter segments were constructed to assess the effect of presence or absence of few selected regulatory elements on expression ability of the promoter. Based on qualitative evaluation of fluorescence, the pGFP-F/VspI showed highest fluorescence followed by pGFP-P, pGFP-F/SpeI, pGFPminimal and pGFP-D.

show abstract

Section: Introductionmentioning

confidence: 99%

Cloning and characterization of ovine αS1-casein gene promoter: A transfection study in rat mammary gland cell line

Bhure

Sharma

2007

DNA Sequence

View full text Add to dashboard Cite

show abstract

“…Sitespecific mutagenesis of the MGF binding site led to complete inactivation of a -300 to + 1 ,B-casein promoter-reporter construct. The second of these interesting regions, originally termed the milk box consensus (17), at -140 to -110, was shown to repress reporter gene expression. Deletion or sitespecific mutagenesis of the milk box region led to increased basal activity of a 3-casein-chloramphenicol acetyltransferase (CAT) construct.…”

mentioning

confidence: 99%

YY1 represses beta-casein gene expression by preventing the formation of a lactation-associated complex.

Raught¹,

Khursheed²,

Kazansky³

et al. 1994

Mol. Cell. Biol.

View full text Add to dashboard Cite

Site-specific mutagenesis of the highly conserved milk box (-140 to -110) region suggested that I-casein expression is regulated by a hormone-mediated relief of repression (M. Schmitt-Ney, W. Doppler, R. K. Ball, and B. Groner, Mol. Cell. Biol. 11:3745-3755, 1991). However, when this sequence was placed upstream of a heterologous thymidine kinase promoter, it activated reporter gene expression. This apparent paradox was resolved when the trans-acting factor YY1, capable of acting as both a positive and negative regulator, was shown to interact with the milk box region, using bacterially expressed WY1 and specific oligonucleotide and antibody competition experiments. Second, it was demonstrated that extracts prepared from several cell types contained a protein(s) interacting with the mammary gland-specific factor (MGF) binding site, previously shown to be required for j-casein promoter activity (Schmitt-Ney et al., Mol. Cell. Biol. 11:3745-3755, 1991 construct. The second of these interesting regions, originally termed the milk box consensus (17), at -140 to -110, was shown to repress reporter gene expression. Deletion or sitespecific mutagenesis of the milk box region led to increased basal activity of a 3-casein-chloramphenicol acetyltransferase (CAT) construct. To date, however, no single binding region which is able to confer proper hormonal regulation of a reporter gene in cells has been characterized, suggesting that cooperative factor interactions may be required for appropriate hormonal regulation of r-casein transcription.To begin to decipher this complex factor interplay, the trans-acting factor-DNA interactions at these two important sites in the 13-casein promoter were further characterized. Initially, the ubiquitous trans-acting factor YY1 (yin and yang 1) (41) was identified in mammary epithelial cell extracts and shown to bind in the ,B-casein repressor milk box region. Second, an MGF DNA binding activity was observed in whole cell extracts (WCE) and nuclear extracts of several different cell types, suggesting that a protein(s) interacting with this site is ubiquitous and not mammary gland specific. Sequence analysis of the MGF binding site revealed a striking similarity to the recently described gamma interferon (IFN--y)-activated sequence (GAS), present in a number of genes (27

show abstract

“…The KAL construct was made by recombining a 5' fragment from a cloned guinea pig a-lactalbumin gene (a gift of Dr. R. Craig) [13] and a subclone of the H-2 Kb gene, derived from cosmid H8 [14]. Details of the construction are given in Fig.…”

Section: Dna Constructs and Transgenic Micementioning

confidence: 99%

Expression of major histocompatibility complex class I antigens at low levels in the thymus induces T cell tolerance via a non‐deletional mechanism

et al. 1992

View full text Add to dashboard Cite

Transgenic CBA (H-2k haplotype) mice expressing the H-2 Kb major histocompatibility complex (MHC) class I gene under control of transcriptional promoter elements from a milk protein gene display high-level H-2 Kb transcription in lactating mammary glands and low-level transcription in skin and thymus of male and virgin female transgenic mice. However, H-2 Kb antigen could be detected only in lactating mammary gland epithelial cells by immunohistological methods. All transgenic mice are tolerant of H-2 Kb since they fail to reject skin grafts from mice expressing H-2 Kb molecules. Furthermore, anti-H-2 Kb cytotoxic responses could not be generated using responder T cells from transgenic mice but T cells from the same mice proliferated, in the presence of interleukin-2, in response to stimulator cells expressing H-2 Kb. Tolerance to H-2 Kb is induced in the thymus since CBA mice grafted with thymus tissue from transgenic mice fail to reject H-2 Kb disparate skin grafts. However, experiments with double-transgenic mice also expressing a T cell receptor with anti-H-2 Kb specificity reveal that tolerance induction is not brought about by elimination of thymocytes bearing H-2 Kb-reactive receptors. Instead, a non-deletional mechanism which results in down-modulation of both CD8 and T cell receptor expression in peripheral T cells correlates with the induction of tolerance in these mice. These data reveal that extremely low levels of self-antigen expression in the thymus are sufficient to induce tolerance via non-deletional mechanisms.

show abstract

Structure and expression of the guinea-pig α-lactalbumin gene

Cited by 44 publications

References 45 publications

Cloning and characterization of ovine αS1-casein gene promoter: A transfection study in rat mammary gland cell line

Cloning and characterization of ovine αS1-casein gene promoter: A transfection study in rat mammary gland cell line

YY1 represses beta-casein gene expression by preventing the formation of a lactation-associated complex.

Expression of major histocompatibility complex class I antigens at low levels in the thymus induces T cell tolerance via a non‐deletional mechanism

Contact Info

Product

Resources

About