INNOVATIVE USE OF NON-MAMMALIAN MODEL ORGANISMS TO STUDY MEMBRANE TRANSPORT

Release Date:  September 26, 2000

RFA:  DK-01-012

National Institute of Diabetes and Digestive and Kidney Diseases
National Institute of General Medical Sciences

Letter of Intent Receipt Date:  February 22, 2001
Application Receipt Date:       March 22, 2001

THIS RFA USES THE "MODULAR GRANT" AND "JUST-IN-TIME" CONCEPTS.  IT 
INCLUDES DETAILED MODIFICATIONS TO STANDARD APPLICATION INSTRUCTIONS 
THAT MUST BE USED WHEN PREPARING APPLICATIONS IN RESPONSE TO THIS RFA.

PURPOSE
	
Abnormalities in membrane transport processes are associated with many 
human diseases such as diabetes, cystic fibrosis, renal tubular 
acidosis, congestive heart failure (hypokalemia), and several 
intestinal disorders, all of which contribute to a major health care 
burden for the United States population.  Many of these membrane 
transport processes are well conserved in lower organisms where the 
genomes are known, which are genetically tractable, and which are 
easily manipulated at the cellular and molecular levels.  Unicellular 
organisms (bacteria, yeast) have been used as overexpression systems to 
provide quantities of wild-type or mutated proteins for 
structure/function studies, or as test tubes for regulatory studies.  
Similarly, non-mammalian model organisms such as Caenorhabditis elegans 
(C. elegans) and Drosophila melanogaster are more complex yet highly 
manipulable systems in which to understand the underlying mechanism, 
regulation, and protein structure of many evolutionarily conserved 
membrane transport processes.  However, to fully exploit these model 
systems, new experimental technologies need to be developed and/or 
existing technologies need to be further refined.  This initiative will 
provide Pilot and Feasibility grants (R21) to utilize non-mammalian 
models to develop reagents, methodologies, and novel approaches to the 
study of membrane transport, especially those membrane transport 
processes involved in diseases of relevance to NIDDK and especially 
those involved and required for normal cell function of interest to 
NIGMS.  Examples of relevance to NIDDK include new highly 
differentiated cell lines (such as tubule cells), mutant organisms, 
electrophysiological or imaging methods to study transporter physiology 
and regulation in vivo; structure-function studies of purified 
homologous proteins or proteins in model membrane systems; 
identification of human homologues to proteins studied in model 
organisms, and the search for novel genes and proteins involved in 
membrane transport of ions and nutrients.

Examples of interest to NIGMS include new vectors for the 
overexpression of membrane transporters and associated membrane 
proteins, refolding and purification strategies of overexpressed 
transporters and novel structural approaches to the elucidation of 
their structures.

HEALTHY PEOPLE 2010

The Public Health Service (PHS) is committed to achieving the health 
promotion and disease prevention objectives of "Healthy People 2010," a 
PHS-led national activity for setting priority areas.  Potential 
applicants may obtain a copy of "Healthy People 2010" at 
http://www.health.gov/healthypeople/

ELIGIBILITY REQUIREMENTS

Applications may be submitted by domestic and foreign, for-profit and 
nonprofit organizations, public and private, such as universities, 
colleges, hospitals, laboratories, units of State and local 
governments, and eligible agencies of the Federal Government.  
Racial/ethnic minority individuals, women, and persons with 
disabilities are encouraged to apply as principal investigators.

MECHANISM OF SUPPORT

This RFA will use the National Institutes of Health (NIH) exploratory 
pilot and feasibility project grant (R21) award mechanism.  Responders 
to this initiative may be new or experienced investigators who are able 
to develop new and innovative approaches to study membrane transport 
proteins.  Generally pilot and feasibility proposals are expected to 
have little preliminary data and are reviewed based on the development 
of hypotheses and supporting literature.  Responsibility for the 
planning, direction, and execution of the proposed project will be 
solely that of the applicant.  The maximum budget request for R21 
applications may not exceed $100,000 in direct costs per year, and may 
not exceed two years for the total project period.  This RFA is a one-
time solicitation.  The anticipated award date is September 30, 2001.

Specific application instructions have been modified to reflect 
"MODULAR GRANT" and "JUST-IN-TIME" streamlining efforts being examined 
by the NIH.  Complete and detailed instructions and information on 
Modular Grants can be found at 
https://grants.nih.gov/grants/funding/modular/modular.htm

FUNDS AVAILABLE
The NIDDK intends to commit approximately $2.5 million and the NIGMS 
$500,000 in FY 2001 to fund approximately 20-24 applications in 
response to this RFA.  Although the financial plans of the IC(s) 
provide support for this program, awards pursuant to this RFA are 
contingent upon the availability of funds and the receipt of a 
sufficient number of meritorious applications. At this time, it is not 
known if this RFA will be reissued.
RESEARCH OBJECTIVES

Background

Membrane transport is essential for almost all physiologic processes, 
and disruption often results in disease or death.  New information, 
emerging from the study of bacterial genomes, has revealed a surprising 
degree of conservation of structure of many important membrane 
transporter families.  A new classification system for transport 
proteins, based on gene sequences from twenty organisms and sorted by 
mode of transport and energy coupling mechanism, protein phylogenetic 
family, and substrate specificity, identified nearly 200 well-
characterized families, and an additional 50 or more deemed 
incompletely characterized.  Distinct categories include primary active 
transporters (23 families); secondary active transporters including 
uniporters, symporters, and antiporters (77 families); and channels and 
pores (115 families). 

Transporters facilitate entry of nutrients into the cytoplasm and 
subcellular compartments.  Interestingly, several nutrients are now 
known to directly influence transporter gene expression.  Transporters 
also provide mechanisms for homeostasis and regulation of metabolite 
concentrations by catalyzing the excretion of end products from cells 
and organelles.  Transporter systems control concentrations of ions at 
levels significantly different from the extracellular milieu; the cell 
requirements of membrane potential, water and ion concentrations, and 
trace mineral co-factors are all dependent on transport mechanisms. 
Furthermore, these systems mediate the active extrusion and uptake of 
drugs and/or toxic substances through both the cytoplasm and cell 
membrane.  Transporters also facilitate the uptake and release of a 
variety of signaling molecules, e.g. hormones, which define unique 
cellular function.

Tremendous progress in molecular biology, genomics, and computer 
technology is resulting in advances in understanding protein structure, 
the substrates and mode of action of various membrane transporters, 
their regulation, and their impact on cellular and organ function.  
Much of this work has been done in bacteria, yeast and cultered cells.  
However, many problems remain to be overcome, and it is likely that 
prokaryotes and both lower and higher non-mammalian model systems, 
including C. elegans and Drosophila, will provide some solutions.  
Among other advantages, their genomes have been sequenced, and they are 
genetically manipulable.  In addition, these organisms lack much of the 
genetic and molecular redundancy found in higher animals, simplifying 
the study of those transporters that are conserved with humans.

Membrane protein structure studies are notoriously difficult because of 
insufficient quantities of pure protein, and because they are usually 
not readily crystallized.  NMR is rarely used to determine structure 
because of the large size of these proteins; however, non-mammalian 
eukaryotic model organisms may contain homologues of important 
transporters that are more easily overexpressed and more easily 
crystallized, yet may be more similar to the mammalian proteins than 
those found in prokaryotes.  In other cases, the prokaryotic model is 
the only one available and tractable for such studies. 

Important insights are also to be expected in studies of regulation of 
transporter activity or regulation via control of transcription at the 
protein level by enzymes or other protein cofactors, through changes in 
substrate affinity, by allosteric metabolites, or via compartmentation 
or movement through the cell.  Changes in transporter activity can be 
in response to hormones, substrate delivery, or other complex 
processes.  Regulation can therefore depend on interactions with other 
organs, on cell machinery or membrane composition, and can be difficult 
to study in far-removed model systems or in isolated cells.  Many 
necessary tools, like genetic manipulation or fluorescence tagging are 
more difficult to use in intact mammals.  Similarly, study of mutated 
model organisms or the sequenced genomes of a variety of organisms may 
yield information about unknown associated protein subunits or 
regulators.  

Objectives and Scope

The purpose of this initiative is to provide Pilot and Feasibility 
grants to fund the development of tools and methods that permit the 
exploitation of non-mammalian model organisms to characterize membrane 
transport in areas of interest to NIDDK.

The following are some examples of the types of investigations that 
would be responsive to this RFA; however, responses need not be limited 
to those areas listed below. 

o new strategies for finding novel transporters and their associated 
molecules; 

o development of isolated cell preparations and cell lines (such as 
renal tubule cells), from genetically tractable non-mammalian model 
organisms, especially those with sequenced genomes; 

o development of forward and reverse genetic strategies for 
characterizing membrane protein structure, function and regulation;

o finding new means of utilizing mutant organisms for the study of 
membrane transport;

o use of model organisms to study changing roles of transporters 
throughout development and among organs;

o finding homologues of important mammalian genes that are more easily 
over-expressed and/or crystallized;

o development of new methods that will lead to the characterization of 
ion channels and other ion transporters and their interacting proteins;

o development or refinement of electrophysiological, electron 
microscopic or imaging methods to be used for assessing membrane 
transport function in the intact organism;  

o development and application of informatic tools for identifying 
membrane transport proteins and studying their function.

It is anticipated that, as a result of the grants funded with this RFA, 
new and innovative approaches will have been developed and will be 
effectively utilized by the investigators to submit competitive 
investigator-initiated R01 research grant applications.  

URLS IN NIH GRANT APPLICATIONS OR APPENDICES
All applications and proposals for NIH funding must be self-contained 
within specified page limitations. Unless otherwise specified in an NIH 
solicitation, internet addresses (URLs) should not be used to provide 
information necessary to the review because reviewers are under no 
obligation to view the Internet sites. Reviewers are cautioned that 
their anonymity may be compromised when they directly access an 
Internet site.
LETTER OF INTENT 

Prospective applicants are asked to submit, by February 22, 2001, a 
letter of intent that includes a descriptive title of the proposed 
research; the name, address, and telephone number of the Principal 
Investigator; the identities of other key personnel and participating 
institutions; and the number and title of the RFA in response to which 
the application may be submitted.

Although a letter of intent is not required, is not binding, and does 
not enter into the review of a subsequent application, the information 
that it contains allows NIDDK staff to estimate the potential review 
workload and plan the review.

The letter of intent is to be sent to:

Chief, Review Branch 
Division of Extramural Activities, NIDDK
6707 Democracy Boulevard, Rm. 653 MSC 5452
Bethesda, MD 20892-5452
(for express/courier service: Bethesda, MD 20817)
Telephone:  (301) 594-8885
FAX:  (301) 480-3505

APPLICATION PROCEDURES

Applications are to be submitted on the grant application form PHS 398 
(rev. 4/98) and will be accepted at the standard application deadlines 
as indicated in the application kit.  Application kits are available at 
most institutional offices of sponsored research, or may be obtained 
from the Division of Extramural Outreach and Information Resources, 
National Institutes of Health, 6701 Rockledge Drive, MSC 7910, 
Bethesda, MD 20892-7910, telephone 301-710-0267, email: 
GrantsInfo@nih.gov; and on the internet at 
https://grants.nih.gov/grants/funding/phs398/phs398.html.

The modular grant concept establishes specific modules in which direct 
costs may be requested as well as a maximum level for requested 
budgets.  Only limited budgetary information is required under this 
approach.  The just-in-time concept allows applicants to submit certain 
information only when there is a possibility for an award.  It is 
anticipated that these changes will reduce the administrative burden 
for the applicants, reviewers, and Institute staff.  The research grant 
application form PHS 398 (rev. 4/98) is to be used in applying for 
these grants, with the modifications noted below.

Budget Instructions

Modular Grant applications will request direct costs in $25,000 
modules, up to a total direct cost request of $100,000 per year. The 
total direct costs must be requested in accordance with the program 
guidelines and the modifications made to the standard PHS 398 
application instructions described below:

PHS 398

o FACE PAGE: Items 7a and 7b should be completed, indicating Direct 
Costs (in $25,000 increments up to a maximum of $100,000) and Total 
Costs [Modular Total Direct plus Facilities and Administrative (F&A) 
costs] for the initial budget period.  Items 8a and 8b should be 
completed indicating the Direct and Total Costs for the entire proposed 
period of support.

o DETAILED BUDGET FOR THE INITIAL BUDGET PERIOD:  Do not complete Form 
Page 4 of the PHS 398. It is not required and will not be accepted with 
the application.

o BUDGET FOR THE ENTIRE PROPOSED PERIOD OF SUPPORT:  Do not complete 
the categorical budget table on Form Page 5 of the PHS 398.  It is not 
required and will not be accepted with the application.

o NARRATIVE BUDGET JUSTIFICATION:  Prepare a Modular Grant Budget 
Narrative page. (See 
https://grants.nih.gov/grants/funding/modular/modular.htm for 
sample pages.)  At the top of the page, enter the total direct costs 
requested for each year.  This is not a Form page.

o Under Personnel, list all project personnel, including their names, 
percent of effort, and roles on the project.  No individual salary 
information should be provided. However, the applicant should use the 
NIH appropriation language salary cap and the NIH policy for graduate 
student compensation in developing the budget request.

Provide an additional narrative budget justification for any variation 
in the number of modules requested.

o BIOGRAPHICAL SKETCH:  The Biographical Sketch provides information 
used by reviewers in the assessment of each individual's qualifications 
for a specific role in the proposed project, as well as to evaluate the 
overall qualifications of the research team. A biographical sketch is 
required for all key personnel, following the instructions below.  No 
more than three pages may be used for each person. A sample 
biographical sketch may be viewed at: 
https://grants.nih.gov/grants/funding/modular/modular.htm.

- Complete the educational block at the top of the form page;
- List position(s) and any honors;
- Provide information, including overall goals and responsibilities, on 
research projects ongoing or completed during the last three years.
- List selected peer-reviewed publications, with full citations;

o CHECKLIST:  This page should be completed and submitted with the 
application. If the F&A rate agreement has been established, indicate 
the type of agreement and the date. All appropriate exclusions must be 
applied in the calculation of the F&A costs for the initial budget 
period and all future budget years.

o The applicant should provide the name and phone number of the 
individual to contact concerning fiscal and administrative issues if 
additional information is necessary following the initial review.  The 
program announcement title and number must be typed on line 2 of the 
face page of the application form and the YES box must be marked.

The RFA label available in the PHS 398 (rev. 4/98) application form 
must be affixed to the bottom of the face page of the application.  
Failure to use this label could result in delayed processing of the 
application such that it may not reach the review committee in time for 
review.  In addition, the RFA title and number must be typed on line 2 
of the face page of the application form and the YES box must be 
marked.

The sample RFA label available at: 
https://grants.nih.gov/grants/funding/phs398/label-bk.pdf has been 
modified to allow for this change. Please note this is in pdf format.
Submit a signed, typewritten original of the application, including the 
Checklist, and three signed photocopies, in one package to:

Center for Scientific Review
National Institutes of Health
6701 Rockledge Drive, Room 1040 - MSC 7710
Bethesda, MD 20892-7710
Bethesda, MD 20817 (for express/courier service)

At time of submission, two additional copies of the application must be 
sent to:

Chief, Review Branch
Division of Extramural Activities, NIDDK
6707 Democracy Boulevard, Rm. 653 MSC 5452
Bethesda, MD 20892-5452
(for express/courier service: Bethesda, MD 20817)

Applications must be received by March 22, 2001.  If an application is 
received after that date, it will be returned to the applicant without 
review. Supplemental documents containing significant revision or 
additions will not be accepted, unless applicants are notified by the 
Scientific Review Administrator.  

The Center for Scientific Review (CSR) will not accept any application 
in response to this RFA that is essentially the same as one currently 
pending initial review, unless the applicant withdraws the pending 
application.  The CSR will not accept any application that is 
essentially the same as one already reviewed.  This does not preclude 
the submission of substantial revisions of applications previously 
reviewed, but such applications must include an introduction addressing 
the previous critique.

REVIEW CONSIDERATIONS

Upon receipt, applications will be reviewed for completeness by the CSR 
and responsiveness by the NIDDK and NIGMS. Incomplete and/or non-
responsive applications will be returned to the applicant without 
further consideration.

Applications that are complete and responsive to the RFA will be 
evaluated for scientific and technical merit by an appropriate peer 
review group convened by the NIDDK in accordance with review criteria 
stated below.  As part of the initial merit review, all applications 
will receive a written critique and undergo a process in which only 
those applications deemed to have the highest scientific merit, 
generally the top half of the applications under review, 
will be discussed, assigned a priority score, and receive a second 
level review by the appropriate National Advisory Council.

Review Criteria

The goals of NIH-supported research are to advance our understanding of 
biological systems, improve the control of disease, and enhance health.  
In the written comments, reviewers will be asked to discuss the 
following aspects of the application in order to judge the likelihood 
that the proposed research will have a substantial impact on the 
pursuit of these goals.  Each of these criteria will be addressed and 
considered in assigning the overall score, weighting them as 
appropriate for each application.  Note that the application does not 
need to be strong in all categories to be judged likely to have major 
scientific impact and thus deserve a high priority score.  For example, 
an investigator may propose to carry out important work that by its 
nature is not innovative but is essential to move a field forward.

o Innovation:  Does the project appear to likely develop novel tools, 
approaches, or methods?  Are the aims original and innovative?  Does 
the project challenge existing paradigms or develop new methodologies 
or technologies?

o Significance:  Does this study address an important problem?  If the 
aims of the application are achieved, how will scientific knowledge be 
advanced?  What will be the effect of these studies on the concepts or 
methods that drive this field?

o Approach:  Are the conceptual framework, design, methods, and 
analyses adequately developed, well-integrated, and appropriate to the 
aims of the project?  Does the applicant acknowledge potential problem 
areas and consider alternative tactics?

o Investigator:  Is the investigator appropriately trained and well 
suited to carry out this work?  Is the work proposed appropriate to the 
experience level of the principal investigator and other researchers 
(if any)?

o Environment:  Does the scientific environment in which the work will 
be done contribute to the probability of success?  Do the proposed 
experiments take advantage of unique features of the scientific 
environment or employ useful collaborative arrangements?  Is there 
evidence of institutional support?

In addition to the above criteria, in accordance with NIH policy, all 
applications will also be reviewed with respect to the following:

o Availability of special opportunities for furthering research 
programs through the use of unusual talent resources, populations, or 
environmental conditions in other countries which are not readily 
available in the United States or which provide augmentation of 
existing U.S. resources.

AWARD CRITERIA

Applications will compete for available funds with all other approved 
applications assigned to the National Institute of Diabetes and 
Digestive and Kidney Diseases and the National Institute of General 
Medical Sciences.  The following will be considered in making funding 
decisions:

o Quality of the proposed project as determined by peer review;

o Availability of funds;

o Program priority.

INQUIRIES

Inquiries are encouraged.  The opportunity to clarify any issues or 
questions from potential applicants is welcome.

Direct inquiries regarding NIDDK programmatic issues to:

M. James Scherbenske, Ph.D., 
Renal Physiology/Cell Biology and 
 Kidney Centers Program Director
DKUHD/NIDDK
6707 Democracy Blvd, Room 613
Bethesda, MD 20892-5458
Telephone:  (301) 594-7719
FAX:  (301)480-3510 
E-mail: scherbensk@extra.niddk.nih.gov

or

Maren Laughlin, Ph.D., 
Metabolism Research Program Director
DDEMD/NIDDK
6707 Democracy Blvd, Room 6101
Bethesda, MD 20892-5458
Telephone:  (301) 594-8802
FAX:  (301)480-3503 
E-mail: LaughlinM@extra.niddk.nih.gov

or

Michael K. May, Ph.D.
DDND/NIDDK
6707 Democracy Boulevard, Room 663
Bethesda, MD 20892-5458
Telephone:  (301) 594-8884
FAX:  (301)480-8300 
E-mail: MayM@extra.niddk.nih.gov

Direct inquiries regarding NIGMS programmatic issues to:

Jean Chin, Ph.D.
CBB/NIGMS
45 Center Drive, Room 2AS.19A
Bethesda, MD 20892-6200
Telephone:  (301) 594-2485
Fax:  (301) 480-2004
E-mail:  ChinJ@nigms.nih.gov

Direct inquiries regarding NIDDK fiscal and administrative matters to:

Mrs. Helen Y.S. Ling
Division of Extramural Activities
NIDDK
6707 Democracy Blvd, Room 629
Bethesda, MD 20892
Telephone:  (301) 594-8857
FAX: (301) 480-3504
E-Mail: LingH@extra.niddk.nih.gov

Direct inquiries regarding NIGMS fiscal and administrative matters to:

Ms. Grace Tuanmu
Division of Extramural Activities
NIGMS
45 Center Drive, Room 2AS.55J
Bethesda, MD 20892-6200
Telephone:  (301) 594-5520
Fax:  (301) 480-2554
E-mail:  TuanmuG@nigms.nih.gov

AUTHORITY AND REGULATIONS

This program is described in the Catalog of Federal Domestic Assistance 
No. 93.821, 93.847, 93.848, 93.849.  Awards are under authorization of 
the Public Health Service Act, Title IV, Part A (Public Law 78-410, as 
amended by Public Law 99-158, 42 USC 241 and 285) and administered 
under NIH grants policies and Federal Regulations 42 CFR 52 and 45 CFR 
Parts 74 and 92.  This program is not subject to the intergovernmental 
review requirements of Executive Order 12372 or Health Systems Agency 
review.

The PHS strongly encourages all grant and contract recipients to 
provide a smoke-free workplace and promote the non-use of all tobacco 
products.  In addition, Public Law 103-227, the Pro-Children Act of 
1994, prohibits smoking in certain facilities (or in some cases, any 
portion of a facility) in which regular or routine education, library, 
day care, health care or early childhood development services are 
provided to children.   This is consistent with the PHS mission to 
protect and advance the physical and mental health of the American 
people.

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