Rabbit Anti-HEYL Rabbit Anti-HEYL

Qty: 100µg/400 µL Rabbit anti-HEYL Catalog No. 40-3500 Lot No. Rabbit anti-HEYL

FORM This polyclonal antibody is supplied as a 400 µL aliquot at a concentration of 0.25 mg/mL in phosphate buffered saline (pH 7.4) containing 0.1% sodium azide. This antibody is epitope-affinity purified from rabbit antiserum.

PAD: ZMD.455

IMMUNOGEN Synthetic peptide derived from the N-terminal region of the human HEYL (Hairy-related transcription factor 3 (HRT3), hairy enhancer-of -split related with YRPW motif) protein, which differs from mouse and rat sequence by one non-conservative amino acid.

SPECIFICITY This antibody reacts with the HEYL protein. On Western blots, it identifies the target band at ~38 kDa.

REACTIVITY Reactivity has been confirmed with human HEYL-transfected NIH3T3 cell lysates and rat heart homogenates by Western blotting and with HUVEC cells infected with adenovirus expressing HEYL by immunofluorescence.

Sample Western Immuno- Blotting fluorescence Human +++ +++ Rat +++ ND (Excellent +++, Good++, Poor +, No reactivity 0, Not applicable N/A, Not Determined ND)

USAGE Working concentrations for specific applications should be determined by the investigator. Appropriate concentrations will be affected by several factors, including secondary antibody affinity, antigen concentration, sensitivity of detection method, temperature and length of incubations, etc. The suitability of this antibody for applications other than those listed below has not been determined. The following concentration ranges are recommended starting points for this product.

Immunofluorescence: 4 µg/mL Western Blotting: 1-3 µg/mL

STORAGE Store at 2-8°C for up to one month. Store at –20°C for long-term storage. Avoid repeated freezing and thawing.

(cont’d)

www.invitrogen.com Invitrogen Corporation • 542 Flynn Rd • Camarillo • CA 93012 • Tel: 800.955.6288 • E-mail: [email protected] PI403500 (Rev 10/08) DCC-08-1089 Important Licensing Information - These products may be covered by one or more Limited Use Label Licenses (see the Invitrogen Catalog or our website, www.invitrogen.com). By use of these products you accept the terms and conditions of all applicable Limited Use Label Licenses. Unless otherwise indicated, these products are for research use only and are not intended for human or animal diagnostic, therapeutic or commercial use. (40-3500 cont’d)

BACKGROUND Heyl is a member of the Hairy/ Enhancer of split (E(spl))-related with YRPW motif (Hey) genes, which are a subfamily of mammalian (E(spl))-related basic helix-loop-helix (bHLH) genes that encode a carboxy-terminal KPYRPWG sequence3. The proteins are also known as hairy-related transcription factors (HRT). Three hairy-related bHLH transcription factor genes were isolated and characterized from mouse and human (HEY1, HEY2 and HEYL). All three HEY genes have a similar genomic structure with five exons7. While the overall structure with the bHLH domain, orange domain and WRPW motif is similar, the last motif is absent in HEYL7. HEYL (HRT3) maps to human chromosome 1p34.37. Hey genes are important transmitters for signals that shape the cardiovascular system during development and possibly in later life1. HEY (HRT) proteins may regulate specific set of cardiac genes by modulating the function of GATA proteins and other cardiac transcriptional activators in a signal-dependent manner4.

HEYL is strongly expressed in the presomitic mesoderm, the somites, the peripheral nervous system and the smooth muscle of the arteries4. HEYL expression overlaps with Notch3 expression in vascular smooth muscle cells and thymus4. Loss of HEYL expression at the level of nascent somites in Notch1 and Delta-Like1 knockout mutants implicates HEYL as a Notch effector during somite formation4. HRT genes are downstream targets for Notch signaling and are part of a negative autoregulatory loop whereby HRT proteins repress their own expression though interference with Notch signaling4.

Invasive breast cancer vasculature induces a high expression level of specific transcription factors, including HEYL that may drive gene expression changes necessary for breast cancer neovascularization6. HEYL is expressed in tumor endothelial cells and is able to both induce proliferation and attenuate programmed cell death of primary endothelial cells in vitro 6.

REFERENCES 1. Fischer A, et al. Trends Cardiovasc Med 13:221-226, 2003. 2. Kathiriya IS, et al. J Biol Chem 279:54937-54943, 2004. 3. Leimeister C, et al. Mech Dev 85:173-177, 1999. 4. Leimeister C, et al. Mech Dev 98:175-178, 2000. 5. Nakagawa O, et al. PNAS 97:13655-13660, 2000. 6. Parker BS, et al. Cancer Research 64:7857-7866, 2004. 7. Steidl C, et al. Genomics 66:195-203, 2000.